US rebalance strategy to Asia and US-China rivalry in South China Sea from the perspective of the offensive realism

Purpose – This study aims to examine the nexus of the US rebalance strategy to Asia and the US–China rivalry in the South China Sea (SCS) from the perspective of the offensive realism theory. Design/methodology/approach – The study depends on the descriptive approach that deals with the analysis and description of the phenomenon. Also, the study uses the qualitative method to analyze the primary sources concerning the rebalance. Findings – The study has found four results: first, the rebalance strategy to Asia is a comprehensive strategy to contain China’s rise. Second, China’s offensive strategy in the SCS since 2008 has been the main driver of launching the rebalance. Third, offensive realism presents a convenient analysis to understand the rebalance, China’s offensive strategy in the SCS, and the US–China rivalry in the SCS. Forth, SCS is one of the most important venues of the US–China rivalry for global hegemony. Research limitations/implications – Limited to the period from 2009 to 2016. The Obama Era. Originality/value – This study highlights the centrality of the SCS in the US–China global rivalry that has not been yet well researched.


Introduction
The implications of China's rise were greatly debated. The offensive realists contend that China is a revisionist power rather than a status quo power as the liberals claim. It seeks to be a regional power in Asia. Offensive realism maintains that the balance of power in the international system in a constant change. This change encourages the revisionist power to pursue the regional hegemony that facilities the global hegemony so as to secure its survival. Therefore, the offensive realism holds that the rise of a potential regional hegemony would not be peaceful at all. Because the dominant power in the international system will strive hard to undermine that potential regional hegemony so as to secure its survival as a global dominant.
In his speech before the Australian parliament on November 17, 2011. President Obama declared the rebalance strategy to Asia. Obama described the strategy as a broad shift of the USA's attention from the Middle East to Asia-Pacific given the huge geostrategic significance of the latter to the US priorities. Rebalance strategy consisted of three main elements, economic, diplomatic and military/security. The latter, by which the USA will undertake a large-scale redeployment of its military power in Asia-Pacific and establish new security alliances has greatly suggested that rebalance was designed to contain China's rise in Asia. Especially, since the financial global crisis in 2008, the global balance of power has gradually become tilted in favor of China. On the other hand, this shift in the balance of power greatly clarifies why China since 2008 has transformed its strategy in the South China Sea (SCS) to a clear offensive strategy in which was intensified under president Xi Jinping.
Thus, this study seeks to analyze the nexus of the US rebalance strategy to Asia and China's strategy in the SCS from the perspective of offensive realism. In this respect, the study examines whether China is a revisionist power or a status quo power, and the significance of the SCS in this regard. The study also examines whether the rebalance is a containment strategy against China's rise, and the significance of the SCS in this regard too.

Offensive realism: ideas and hypotheses
In his book, The Tragedy of Great Power Politics. John Mearshimer offered the offensive realism theory to challenge the defensive realism. While the defensive realism holds that the main goal of states is to maximize its power for security so as to secure their survival. The offensive realism affirms that the maximization of power is for hegemony rather than the security to secure their survival in the anarchy system. Thus, the defensive realism has a more optimistic vision than the offensive realism for the international system because it holds that the security is abundant.
The focus of the offensive realism only on the rivalry among the great powers in the international system. Mearsheimer (2001), the rivalry among the great powers for hegemony is a constant feature in the international system. Because of this hegemony the best way to secure their survival (Mearsheimer, 2001, p. 29). In this way, the offensive realism holds a pessimistic vision of the international system. Because the rivalry among the great power for hegemony is endless. Where the great powers forced permanently to adopt offensive and expansionist military strategies whenever possible to secure their survival (Wong, 2016, p. 41). These strategies would be containment or preventive wars or offshore balance to undermine the potential threatening power (Goswami, 2013, p. 7).
The offensive realism presents five hypotheses to prove that the pursuit of the hegemony is the ideal way for the great powers to secure their survival: H1. The anarchy of the international system. The offensive realism takes a more severe view on the anarchy than the rest of the realism theories. Where the offensive realism argues that the absence of a central government in the international system not only force the states to maximize their power but also stimulates the states to exploit any opportunities to acquire power at the expense of the other states.
H2. Great powers possess some of the offensive military capabilities to destroy each other. In this regard, the internal balance and the offensive strategies among the states are a persisted process.
H3. States cannot be absolutely sure of the others' intentions, particularly with possessing the offensive capabilities. The offensive realists contend that the expecting of a good intention of the other states permanently is unreasonable and impossible uncertain because the leaders always lie.
H4. Great power is rational actors. Where the goal of survival forces them to be very cautious when developing their offensive strategies.
In addition, the aforementioned, the hallmark of offensive realism lies in its focus on the balance of power in the international system. Where it holds that the main trait of the balance of power in the international system is the persistent change given the persistent change of the states' capabilities too. Meanwhile, the offensive realism maintains that the international system is full of dissatisfied or revisionist great powers in which surely will exploit the change of the balance of power to challenge the dominant to achieve the global hegemony (Mearsheimer, 2001, p. 2). Therefore, the offensive realists built their prediction about the inevitability of the US-China rivalry based on the truth of the balance of power. They hold that the US global hegemony is exceptional and temporary in the international system. While China's comprehensive capabilities are steadily rising and has a powerful desire to be a regional hegemony in Asia as it a revisionist power (Goswami, 2013, p. 9). The truth of the shift in the balance of power greatly supports that the rebalance is a new stage in the rivalry in the international system between the USA and China.
3. Offensive realism, China's rise and the South China Sea 3.1 Offensive realism and China's rise The offensive realists, including Mearsheimer, paid much attention in their work more than others did on China's rise and its implications on the US global hegemony. China's rise has been much debated between the realists and the liberals. The main debate regarding China's rise revolved around this question, does China's rise actually peaceful? While the liberals hold that since China had accepted to work within the liberal economic system led by the USA in the 1990s. It has become a status quo power because it finally embraced the liberal values, as well as there are many factors support peace of China's rise such as its non-imperial history and the peacefulness of the Confucian teachings. On the other hand, the offensive realists maintain that China's rise would be not peaceful because of it a revisionist power (Teixeira, 2018, pp. 25-26). The offensive realism counts on the historical narrative of the rising power to justify that China is a revisionist power. Where the history indicates that the rising power usually is a revisionist power seeks to challenge the dominant such as Nazi Germany and Japan prior to the second world war (Bjällstrand, 2014, p. 8). According to Mearsheimer (2014), despite its liberal discourse and the slogan of the peaceful rise. China is a revisionist power seeks to be a regional hegemony in Asia, and alter the balance of power in its favor by imposing a "Chinese Monroe" to expel the USA from Asia. In this respect, he also argues that the continuation of the huge rates of china's economy will inevitably be translated into military might. Such might well galvanize China for regional hegemony in Asia completely. This regional hegemony will also enable China to expand its presence globally, including militarily, even in areas of the USA's strong influence or presence. Moreover, it will enable it to impose its terms on regional disputes (Mearsheimer, 2014).
In fact, there are many evidences support Mearsheimer's predictions. For instance, in terms of the shift in the balance of power. Arguably, the three decades of the growing economic development placed China as the second largest economy in the world. The economic estimations assert that China's economy would be the number one by 2020 (Logan, 2013, p. 2). However, the most importantly, China since the 2000s, has been translating this economic power to military might and global influence. For instance, China tripled its military spending during the period from 2000 to 2011 (Mislan, 2017). In fact, this huge spending on military power means the compromise the balance of power in Asia in favor of China. On the other hand, it gives an indication that China actually seeks to be a regional hegemony.
The assertiveness and strictness of China's foreign policy, particularly in the SCS since 2008, are another important indication of the Mearsheimer's predictions. Moreover, China's foreign policy since 2008 has become a more stringent in many flashpoints issues with the USA such as climate change, North Korea, Taiwan and Iran (Anderson and Cha, 2017, pp. 605-606).
3.2 China's offensive strategy in the South China Sea and regional hegemony in Asia 3.2.1 South China Sea and China's regional hegemony in Asia. The offensive realists, Mearsheimer included, maintain that China's assertive behavior in the SCS is the main indicator that China is a revisionist power that seeks to be a regional hegemony in Asia. In this vein, SCS plays a vital role in China to achieve regional hegemony.
China's regional hegemony heavily depends on its economic power. In this vein, SCS with its huge reserves of oil and natural resources. In addition, most of China's trade passes the SCS, including oil shipments, plays an essential role in China's regional power (Fravel, 2011, p. 296). On the other hand, China's strong foothold in the SCS secures an expansion of the Chinese maritime maneuver in the Asian seas. This expansion will enable China to dominate the Asian economy and the trade routes in Asia, as well as resolve its sovereignty disputes, including in the South and East China Seas based on its own terms. Most importantly, it will enable China to extend its influence beyond Asia to achieve global hegemony (Kuntic, 2015, pp. 250-251). In addition, China's naval powerful presence in the SCS will greatly shift the total military balance of power in China's favor. (Rolf and Agnew, 2016, p. 253). For these reasons, SCS is very vital for China to achieve full regional hegemony. This truth is very evident from China's offensive strategy in the SCS since 2008.
3.2.2 China's offensive strategy in the South China Sea. China had long had a strategy to preserve its claims in the SCS. However, this strategy was prominently defensive. In 2002, China signed on the Declaration on the Conduct of the Parties in the SCS. In which stipulated to prevent the actions leading to escalating the conflicts in the SCS. Arguably, since 2008, China's strategy in the SCS has become prominently offensive. Where it extremely violated the declaration through very assertive or violent policies. For instance, in 2008 China has disrupted Vietnam's oil exploration cables. Moreover, it threatened for the first time to expel the American oil companies operating on the coast of Vietnam (DeLisle, 2016, pp. 146-147;Widian and Arimadona, 2018, p. 92).
The most importantly, in 2008 China has submitted the nine-dash line map to the UN, to affirm its exclusive mandate on almost 90 per cent of the disputed Islands with the claimant states based on lawful and historical claims. In 2009, China has officially deemed the map as its official maritime boundaries in SCS (Nacht et al., 2018, p. 80). Broadly speaking, the map has sparked the china official's tone of considering SCS as a "core interest" since 2010, which reflects the core of China's new offensive strategy in the SCS (Lanteigne, 2019).
Furthermore, China's offensive strategy in the SCS did not exclude the USA. In 2009, Chinese vessels aggressively maneuvered the USNS impeccable and the USNS victorious when they were on a routine surveillance operation in the SCS. China wanted through the two incidents to challenge the United Nations Convention on the Law of the Sea UNCLOS, and the US military activities in the SCS, in particular, the US surveillance program (Cordesman, 2014, p. 484;Lanteigne, 2019). In fact, China's offensive strategy in the SCS since 2008 supports the offensive realism's account, especially regarding the impact of the change of the balance of power on the behavior of the revisionist power. On the other hand, it underpins the offensive realists' predictions in which assert that China is a revisionist power. In addition to, SCS is very vital to China to achieve regional hegemony. Therefore, the rebalance as a containment strategy of the dominant (USA) towards China is logical according to the offensive realism's account.
3.2.3 Xi Jinping's offensive strategy in the South China Sea. President Xi Jinping constitutes a turning point in the history of China's foreign policy. He came to the power bearing an irreversible determination to compete for the superiority of the international system.
Since 2013, Xi Jinping has been attempting to achieve the full regional hegemony in Asia through, for example, the Silk Road initiative and the Asian Infrastructure Investment Bank (Ataka, 2016, p. 80). This evidence renders the SCS is the main pillar for Xi Jinping to achieve the regional hegemony. Morton asserted that china's endeavor to the regional and global leadership under Xi Jinping makes it imperative to the hegemony of the SCS at any cost. Without this hegemony, for instance, China would have not a global naval power, which essential for China to be a superpower (Morton, 2016, p. 910). That is, why; Xi Jinping has adopted a very offensive strategy in the SCS embodied in three very assertive and expansionist policies: Has also revealed China's endeavor for a wider maritime presence in the SCS to protect its core sovereign maritime interests (China's Military Strategy, 2015). In fact, the two documents have shown Chinese determination to "undermine the US naval presence or deter it from further intervention on China's sovereign islands in the SCS, which is reinforced by a rebalancing strategy" (Boje, 2016, p. 35). That is why in 2013 China has established an air defense identification zone on Senkaku Island. (Ham et al., 2016, pp. 13-14). Also, in December China had sent for the first time aircraft carrier Liaoning in the SCS. In the same year, China issued a decree to assemble all the naval entities in one administrative body directly supervised by the government (Broderick, 2015, p. 6). Furthermore, In February 2016, China had set up Advanced HQ-9 surface-to-air missiles in the disputed Island Woody in the SCS. In May and August 2016, China held two major military exercises in the SCS for power projection. Moreover, China increased the dozens of combat vessels and patrol ships in the SCS for a more domination and power projection (Andersen and Perry, 2017, pp. 25-27;Babbage, 2017, p. 20).
3.2.3.2 Bullying and imposition of de facto policy. Bullying against the disputed states like preventing their ships from fishing and the operating activities in the disputed islands; has become since 2013 a deliberated approach by China to impose its sovereignty on its claims in the SCS as de facto (Zhang, 2017, pp. 443-444). However, the most dangerous bullying of China was against the international law, when it rejected on the rule of the Permanent Court of Arbitration, in the SCS case on July 12, 2016, which completely nullified china's historical and legal claims in the SCS, particularly under the nine-dashed map. The court issued a unanimous decision under UNCLOS. Thus, China's response to the decision has confirmed its high arrogance against international legitimacy and law, where it considered the decision is null and not binding to China. It is worth to note that China signed on UNCLOS in 1992, and claims that it is a responsible state in the international community (French, 2017, pp. 49-53).
3.2.3.3 Reclamation and build the artificial islands. Reclamation and build the artificial islands or the expansionist policy is the most dangerous policy of china to tighten its control over the disputed islands or at best to strengthen its sovereignty claims under the ninedashed map. The expansionist policy considers also kind of bullying and the imposition of de facto policy. However, China usually justifies it under several pretexts. For instance, the disputed states, especially the Philippines, Vietnam and Malaysia have also undertaken reclamation activities. Anyhow, since 2013, China undertook unprecedented reclamation activities, especially on Spratly and Paracel atolls. During 2013-2015 China has managed to reclaim more than 3,200 acres of the coral reefs in Spratly and other atolls for forming mega artificial islands. Most importantly, China uses these artificial islands to upgrade its military situation in SCS. Where since 2015, it has proceeded to supply the artificial Islands with advanced military capabilities such as radars, anti-aircraft and airstrips (Lunn and Lang, 2016, pp. 14-16;Zhang, 2017, pp. 445-446;Broderick, 2015, p. 5). The truth is that Xi Jinping's offensive strategy in the SCS has shown that SCS plays an important role in his endeavor for regional hegemony. On the other hand, his strategy proves that SCS actually the core of the US-China rivalry for global hegemony. Thus, rebalance greatly focused on undermining China's strategy in the SCS.

Rebalance and China's rise
The question of the rebalance as a containment strategy directed to China's rise has been much debated. In his discourse before the Australian parliament on November 17, 2011, Obama stressed on a constructive relationship with China within the rebalance he also welcomed to the peaceful rise of China (Obama, 2011). Hillary Clinton also asserted that in her article in foreign affairs magazine October 2011 (Clinton, 2011). Panetta in December 2012 penned an important article about the rebalance in which he emphasized the views that argue the rebalance is mainly to contain China are not sound where the constructive and stable military relationship with China is essential within rebalance (Panetta, 2012). It seems that the US officials attempted as much as possible to deny that the rebalance is a containment strategy. Nevertheless, when considering the time and the location of the rebalance, as well as its focus on the huge redeployment of the US military power in Asia-Pacific, and forming of new security alliances. We find that the rebalance is a containment strategy against China's rise, according to the logic and predictions of offensive realism.
The offensive realism holds that the shift in the balance of power stimulates the revisionist power to achieve the regional hegemony in which imperative to the global hegemony. Conversely, the existing dominant will strive strongly to undermine the revisionist power's endeavor to be a regional hegemony. In this vein, the offensive realism argues that practically the global hegemony as a physical or military expansion is impossible to be achieved by any super power. However, the great powers can secure the superiority in the international system through achieving the full regional hegemony in its regional surroundings, as well as works strongly and permanently to prevent any potential power to be a regional hegemony. In fact, the previous analysis greatly explains the time and the location of the rebalance, hence, the rebalance is a containment strategy against China's rise. Where its location in Asia in which China since 2008 has been attempting to dominate it because of the shift in the balance of power. From his observation of US history, Mearsheimer argues that the USA did not absolutely accept a regional hegemony. It attempted strongly to undermine it to preserve its global position. For instance, the US intervened in the Second World War to undermine Nazi Germany and Japan. Likewise, it adopted a containment strategy to undermine the Soviet Union's power. Thus, he asserts that the USA will never accept that China is a regional hegemony in Asia and will attempt strongly to contain or undermine it in Asia (Mearsheimer, 2001, p. 4;Mearsheimer, 2014). In this respect, DOD document: Sustaining US Global Leadership: Priorities for 21st Century Defense of 2012. Has tied between the Asia-Pacific and the continuation of US global leadership, as well as referred to China as a potential rival that compromises the US economic and security interests in Asia (DOD, Sustaining US Global Leadership, 2012). Additionally, the National Security Strategy of 2015. Has acknowledged the competition with China in which entails the continuation of US strong leadership through enhancing the US military presence (National Security Strategy of the United States of America, 2015).
As for, the military/security element of the rebalance, it has also consistent with the offensive realism's logic regarding the balance strategies of the great powers. The offensive realism characterizes the balance in which the balancer bears directly the burden of maintaining the balance of power. This strategy very clear in the huge military redeployment of the rebalance to undermine China's rise. On the other hand, the offensive realism indicates to the offshore balancing, in which the balancer forges wide alliances for balancing and combat with the threatening power if necessary. This strategy very clear also from the large scale of the US security alliances that included the most Asian countries hostile to China like India, and the SCS countries. In fact, Mearsheimer predicted for the US offshore balancing because of the growing fears of the Asian countries from China's rise (Mearsheimer, 2001, pp. 156-157;Murray, 2015, p. 11;Scott, 2018, p. 20). Therefore, the military/security element of the rebalance clearly targeted to undermine China's rise in Asia, especially its military power and presence. In this vein, Cohen and Ward (2013), contend that China's rising power, especially its military power will inevitably lead to weaken the US superiority in Asia, accordingly its global hegemony. According to them, the US maritime power within rebalance is the basic to contain china (Cohen and Ward, 2013). Ross (2012) also argues that it is a very clear that the military/security axis of rebalance geared to contain China's rise. Indeed, the growing rise of China in Asia has largely doubled the suspicions of the US's allies about the US's readiness or ability to face China (Ross, 2012). Against the backdrop, we can conclude that the rebalance is actually a containment strategy geared to China's rise. However, the most importantly in this regard is to focus on the strategic significance of the SCS for the US global hegemony. In fact, SCS greatly explains the nexus of the US global hegemony and rebalance.

South China Sea and US global hegemony
As noted earlier, China's domination in the SCS is imperative to achieve the regional hegemony, especially under Xi Jinping. However, for the USA, undermining China's ambitions in the SCS does not only lie only in preventing China from being a regional hegemony but also the most importantly is to preserve its global hegemony. This logic, which the author agrees with, suggests that China's offensive strategy in the SCS since 2008 has been the biggest mover for the Obama administration to launch the rebalance. In 2009, Jeffrey Bader stated China's remarkable escalation in the SCS forces the USA to develop a new comprehensive policy in Asia (Fravel, 2014, pp. 4-5). Furthermore, in 2012, the US-China Economic and Security Review Commission indicated that the Chinese pressures to impose its private interpretation on the freedom of navigation in the SCS would undermine the US military presence in Asia (Steffens, 2013, p. 99).
US has long been enjoying a maritime superiority in the SCS. Also, it justifies this naval presence based on the principle of the freedom of navigation of UNCLOS. Indeed, this superiority secures to the USA a lot of vital strategic interests essential to preserve its global hegemony. Economically, the SCS represents one of the main passage of US commerce in which an estimated one billion annually. On the other hand, the SCS contains huge reserves of oils, gas and natural resources. Additionally, the SCS countries are a big market for US goods and investments. On the strategic and military level, the SCS is a vital passage to the US military ships to travel to the most important sites of American influence and interests such as the Indian Ocean, the Arabian Gulf and Central Asia. Furthermore, the US powerful presence in the SCS secures to contain its potential adversaries or competitors such as Russia, India and China of course. Additionally, the USA has other significant interests in the SCS, such as, preserving its security commitments to its allies in particular, Japan and South Korea, as well as containing the radicalism (Gonçalv, 2018, p. 29;Hussain and Tabbasum, 2014, pp. 4-5;Fravel, 2014, pp. 2-3).
The previous facts, significantly underpins why China's offensive strategy in the SCS constitutes the biggest threat to the US global hegemony. Hence, the rebalance was launched on this basis. There are analyses rejecting on this logic. For instance, Shulong (2014) contends that the escalating situation in the SCS since 2008 has been just the US's pretext to justify the rebalance to contain China's rise (Shulong, 2014). However, in all cases, it was destined for the SCS to be crucial to the US-China rivalry for the global hegemony.

Elements of rebalance and China containment
5.1 Military element 5.1.1 Expand and redeployment of the US maritime power in the east and west of Asia. The maritime power has constituted the core of the military strategy of rebalancing. In the context of launching the rebalance, the head of the US naval power, Admiral Jonathan Greenert, has highlighted three main tasks of the US naval: first, deployment and stationing of a more of the naval units in Asia-pacific. Second, promoting the capabilities of these units to be prepared for any upcoming war. Finally, enhance the naval military cooperation with the allies in Asia-Pacific, as well as establish new other partnerships (Furgacz, 2014, pp. 107-108). The first phase of the expanding maritime deployment in Asia-Pacific was the redeployment of the US marine corps in the Australian strategic bases overlooking the Pacific Ocean in 2011. In addition, stationing set of new combat vessels in Singapore's coast (Southgate, 2017, p. 5). Also, within the rebalance, DOD re-processed submarines in the Indian Ocean, South Korea and the Philippines to be ready for "cruise missile attack surfaced" (Sutter et al., 2013, p. 7).
During the Annual Shangri-La Dialogue June 2012, secretary of defense, Leon Panetta, stated that "in the context of rebalance, the US maritime will be redeployed between the Atlantic and Pacific Ocean 60/40 per cent in favor of the Pacific by 2020, instead of the previous 50/50 per cent for both." He also added, "in the coming years, the DOD will increase of numbers of aircrafts, submarines, combat vessels and the numbers of naval maneuvers in the Pacific" (Panetta, 2012). It seems from Panetta's statements that the aim is to undermine any potential growth of China's maritime presence in the Pacific, as well as the SCS. In addition, the persistence of the US maritime hegemony in the SCS greatly limits China's expansion in the Indian Ocean, which represents the key factor of the China's supplies of the commerce and oil, as well as the expansion of its naval power in Asia (Kuntic, 2015, p. 253).
5.1.2 Air-sea battle concept. In June 2012, Panetta declared that "in light of the advanced weapons in the Asia-Pacific in which hinders our maritime access. The USA is currently proceeding to deploy the Air-Sea Battle Concept (ASB)" (Panetta, 2012). In 2013, DOD released ASB document. According to the document ASB is a very advanced concept to face Anti-access/area denial -A2/D2 of the foe in which largely constitutes a challenge to the combat leverage of the USA and our allies in Asia, and it would turn the security equation in the region in foe's favor completely (US DOD, Air-Sea Battle, 2013). The ASB was designed to strengthen the strategic position of the US forces in the Pacific in any potential battle with China. The ASB does not set of weapons, but a strategy based on the strict coordination and integrate the capabilities among the US forces in Asia at any battle. Such coordination is so necessary with the broader expansion and redeployment of the US forces within Rebalance (Furgacz, 2014, p. 114).

Economic element
The truth is that weakening China's economic power is very essential to undermine China's rise. The economic element of the rebalance focused on the Trans-Pacific Partnership (TPP). During his first Asian tour in November 2009, Obama reiterated the US commitment to join TPP. In 2010, the US negotiation to access has begun and after tough talks, TPP was signed in 2015 by members to become the biggest regional treaty for free trade ever signed (Cheng and Chow, 2014, pp. 115-116). TPP constitutes a turning point to the US economy, in terms of the increase of the US exports, new opportunities for investments, and the provision of almost 4 million jobs to Americans (Parker and Anderson, 2016, pp. 10-11). Most importantly, TPP serves as an economic NATO in Asia to disengage the strong economic ties between China and the Asian states (Li, 2014, p. 139). Where China was deliberately excluded by The USA from the partnership talks (Southgate, 2017, p. 8).

Diplomatic element
The US's powerful engagement with Asia's forums and organization represented one of the US methods to undermine China's diplomatic influence in Asia. In which was excessively broadened within those organizations in the past decade, especially in the Association of Southeast Asian Nations (ASEAN) because of the weak engagement of the USA (Manyin, 2012, pp.17-19). In July 2009, the secretary of state, Hillary Clinton has signed with the ASEAN on The Treaty of Amity and Cooperation in Southeast Asia (TAC). As then, the USA has become a permanent participant in the annual ASEAN defense ministers' meeting (ADMMPlus). In another development, President Obama appointed in November 2011 the first US permanent ambassador to the ASEAN. In November 2015, the relationship between ASEAN and the USA has been upgraded to a strategic partnership level. It can be said, the US engagement has greatly been welcomed by ASEAN's members because of their panic of China's escalating behavior in the SCS (Lai and Troxell, 2018, pp. 48-49;Southgate, 2017, p. 9). In 2011, president Obama, as the first American president ever, attended the East Asia Summit (EAS). On the other hand, the US broadened its participation and cooperation in many fields with Asia-Pacific Economic Cooperation (APEC) (Stewart and Reininger, 2016, pp. 33-34;Manyin, 2012, p. 18).

South China Sea within rebalance elements
Undermining China's offensive strategy within rebalance has focused mainly on: 6.1 Security maritime alliances with Vietnam and Philippine US-Vietnam relations are powerful since 1995. Indeed, Vietnam's fears of China's ambitions in the SCS have been the main cause of this strong relationship with the USA. Within the rebalance, the relations have been upgraded to a security maritime alliance. In 2010, the two states have agreed on the annual mutual maritime visits, as well as the annual defense dialogue (Fravel, 2014, p. 8). Faced with the rise of China's threats in the SCS the comprehensive partnership has been declared in July 2013. Followed by signing on the joint vision statement in July 2015, which paved the way for a more US maritime presence in the SCS. For instance, in 2016, the USA increased its maritime presence in Cam Ranh Bay that very close to Vietnam's disputed islands with China in the SCS (Kikuchi and Arakaki, 2017, p. 208;Marston, 2016).
The military alliance between the USA and the Philippine since 1951, is one of the most important security alliances to the USA in Asia. The alliance also was cemented in the past two decades because of the developments in the SCS (Greitens, 2014, pp. 1-2). Nevertheless, the most important development in the path of the alliance was within the rebalance in 2014, by concluding the Enhanced Defense Cooperation Agreement (EDCA). Indeed, EDCA, has come because of the very aggressive behavior of China in the SCS under Xi Jinping. Therefore, under EDCA, the Philippine government allowed the USA to rent four air bases located very close to the Philippines' disputed islands with China in the SCS. Additionally, within EDCA, the two states agreed in 2016 on the annual joint naval exercises in the SCS, known as "Balikatan" (Vicedo, 2017, p. 3;Kikuchi and Arakaki, 2017, p. 207).

Freedom of navigation operations
Arguably, freedom of navigation operations (FONOPs) was deemed the explicit and direct challenge of the USA against China's strategy in the SCS within the rebalance. The freedom of navigation program was founded in 1979, to enhance the US conception of navigation freely in the high seas as being an international common. As its foundation, FONOPs has been targeting challenge to the freedom of navigation by any party, not China only.
Since October 2015, until October 2016 DOD executed four FONOPs in the SCS. The first, USS Lassen operation, on October 27, 2015, where USS Lassen navigated less than 12 nautical miles near some of China's artificial islands built in Spratley. The second, USS Curtis Wilbur operation, on January 30, 2016, where it sailed innocent passage to the depth of the 12 miles of Triton Island. The third, USS William P Lawrence operation, in May 2016, where sailed innocent passage to the depth of the 12 miles near to the Fiery Cross Reef in the Spratly Islands in which China was building airstrip length of 3,000 m. The fourth, Carrier Strike Group USS John Stennis, on October 2016, which navigated within the distance of 12 nautical miles in one of the China's artificial islands in Spratly Island (Pedrozo, 2018, pp. 100-107;Kuok, 2016, pp. 15-18;LaGrone, 2016;Lamothe, 2016). In this vein, Boje (2016), pointed out that these operations were a response of four excessive maritime claims from China: (1) The requirement of the prior notification of innocent passage in China's EEZ.
(2) China's criminalization of the surveillance activities of foreign vessels in China's EEZ. Additionally, The Asian-Pacific Maritime Security Strategy of 2015, stated the FONOPs mainly pursue to challenge any excessive maritime claims in which contrary to UNCLOS. Including the restrictions on surveillance activities in the EEZs. The document also stated, any excessive claims without challenging, particularly in the EEZs, would immensely restrict the passage of US maritime in most oceans around the world (US DOD, The Asian-Pacific Maritime Security Strategy, 2015).

Conclusion
The study has mainly sought to examine the nexus of the US rebalance strategy to Asia and China's strategy in the SCS from the perspective of offensive realism. The offensive realism theory focus on the rivalry among the great powers in the international system. This rivalry mainly for the purpose of hegemony as the ideal method of the great powers to secure their survival. The offensive realism also holds that the shift in the balance of power in the international system certainly creates a severe rivalry between the dominant power and the revisionist power. On the other hand, the offensive realists predicted that China is a revisionist power seeks to be a regional hegemony in Asia.
Arguably, the nexus of the US rebalance strategy to Asia and China's strategy in the SCS greatly reflects the assumptions and predictions of offensive realism. In fact, the shift in the balance of power since 2008 has clarified that there is a new stage of the rivalry between the USA and China for global hegemony. The SCS, in particular, has confirmed that China is a revisionist power seeks to be a regional hegemony in Asia to secure its survival as a global hegemony. Conversely, this truth greatly clarifies also that the rebalance is a containment strategy directed to China as a revisionist power that appeared since 2008 because of the shift in the balance of power. The elements of the rebalance, particularly the military/ security element greatly focused on undermining China's offensive strategy in the SCS. Considering that the latter is very vital to the USA to preserve its influence in Asia, then to secure its survival as a global hegemony.
The author of the study agrees with the analysis in which tends to that the SCS has become the core of the US-China rivalry for global hegemony. In fact, the very violent and expansionist strategy of the president Xi Jinping greatly supports these analyses. Also, the strategy of Xi Jinping has an offensive realist logic. Because it reflects a wide shift in the balance of power in China's favor, particularly in Asia. Needless to say, SCS under Xi Jinping is the main pillar for China's global superiority. Xi Jinping has not hidden his aspiration for China to be a global power.
Therefore, the severe security rivalry between the USA and China, which may develop to a direct military confrontation over the SCS is likely possible in the future. The offensive realism maintains that the great powers are rational actors when developing offensive strategies. This assumption may explain why the rivalry between the USA and China in the SCS has not developed into a military confrontation within the rebalance. Because simply, the USA within the rebalance managed to adjust the balance of power in Asia its favor partially. However, the rebalance could not contain China's rise in Asia and China's offensive strategy in the SCS completely. The president Trump attempts hardly to adjust the balance of power between the USA and China through the SCS in line with the trade war. On the other hand, China strongly resists against these attempts. We can notice that under Trump the degree of the US-China escalation in the SCS is higher than under Obama. These facts suggest that SCS is crucial in deciding the balance of power between the USA and China. Also, the possibility of a military confrontation over the SCS is likely for the considerations of the balance of power between the USA and China in Asia. However, the two powers are still rational yet. The reason may be because the gap in the balance of power has not been seriously widened for both of them.