Editor's Note: The following article is an abstract from a report by the National Institute for South China Sea Studies, headquartered in Haikou, capital of South China's Hainan province.

The United States' military deployments and activities in the Asia-Pacific region are important manifestations of its "rebalancing" strategy. Since President Barack Obama took office in 2009, the US global military strategy has been shifting its focus and giving priority to the region. In 2012 and 2013, it officially announced that 60 percent of its naval vessels and 60 percent of its air force would be deployed in the Asia-Pacific region by 2020. Driven by this rebalancing toward the Asia-Pacific, the US has gradually built up its troop deployments, forward presence and military activities in the region, and increased military cooperation with its regional allies and partners, such as Japan and Singapore.

I Military expenditures, bases and deployment

The proposed US defense budget for fiscal year 2016 was $585.3 billion, an increase of about 4 percent on the budget for the previous fiscal year. In February 2016, the US Department of Defense released a proposed budget request of $583 billion for fiscal year 2017, which is almost the same as that for the previous fiscal year.

By 2015, the US had 368,000 military personnel in the Asia-Pacific region, among whom about 97,000 are stationed to the west of the International Date Line. The military personnel deployed in the Asia-Pacific region account for more than 50 percent of its total military forces overseas.

II Military activities

With the implementation of its rebalancing to the Asia-Pacific strategy, the US has deployed advanced reconnaissance aircraft, unmanned aerial vehicles, electronic surveillance ships, nuclear submarines, orbit reconnaissance satellites, etc. China has become the No 1 target for the US' close reconnaissance in terms of frequency, scope and means. According to available statistics, the US made more than 260 close reconnaissance sorties against China in 2009. The number was more than 1,200 in 2014, and there was an obvious increase in US' close reconnaissance activities in the South China Sea region in 2015. Such activities threaten China's national security, damage China's maritime rights and interests and undermine Sino-US strategic mutual trust. They could also lead to accidental collisions at sea or in the air, making such reconnaissance an important negative factor affecting Sino-US relations and also peace and stability in the region.

Regarding naval operations, more than 700 patrols were conducted by US vessels and aircraft in the South China Sea region in 2015. It is noteworthy that recent US patrols in the South China Sea have been accompanied by a lot of media hype and high-profile assertions they are freedom of navigation operations, a phenomenon not seen anywhere else.

The US has also raised the frequency, scale and complexity of its joint military exercises in the Asia-Pacific region. In 2014, US Pacific Command initiated 160 bilateral and multilateral military exercises in the region. The number of military exercises rose to 175 in 2015. In recent years, the content of the joint exercises has expanded and they now include ground warfare, aerial warfare, maritime warfare, anti-missile warfare, and special operations, as well as electronic and cyber warfare.

III US alliances, partnerships and military cooperation

Japan plays an important role in supporting the US' dominance in the Asia-Pacific. At present, the US has more than 100 military facilities, around 50,000 military personnel, and plenty of advanced weaponry and equipment in Japan. In October 2015, the flagship nuclear-powered aircraft carrier USS Ronald Reagan was deployed to Japan.

In the Republic of Korea, the US has the second-largest military presence in Asia. In June 2015, the US approved an arms sale worth $1.91 billion to the ROK. In March 2016, the US announced that it had reached an agreement with the ROK on deploying the Terminal High Altitude Area Defense, or THAAD, anti-missile system in the ROK, professedly to counter missile threats from the Democratic People's Republic of Korea.

The Philippines has been an important ally of the US in Asia for decades. In April 2014, the US and the Philippines further deepened their military cooperation by signing a 10-year Enhanced Defense Cooperation Agreement in which the Philippines broke its constitutional restraints and allowed the US to use its military bases through rotational deployment.

The US-Australia military alliance is an integral part of the US alliance system in Asia-Pacific. In November 2011, US President Barack Obama and then Australian Prime Minister Julia Gillard jointly announced two Force Posture Initiatives, which allowed the US to deploy 200-250 Marines in Darwin for around six months at a time on a rotational basis starting from 2012, and increased rotation of US aircraft. In 2014, the US and Australia officially signed a 25-year Force Posture Agreement, which provided the legal basis for US military presence in Australia.

The US has also deepened its alliance with Thailand as it has rolled out its rebalancing to the Asia-Pacific. The two countries signed the Joint Vision Statement for the Thai-US Defense Alliance in 2012.

The US has always considered Singapore as an important partner in Asia thanks to Singapore's unique geographical location. Changi Naval Base and Paya Lebar Air Base have become the largest and most important footholds for the US in the South China Sea region. In December 2015, the United States and Singapore signed an Enhanced Defense Cooperation Agreement for the deployment of P8-A anti-submarine patrol aircraft in Singapore for the first time.

The US has been improving its military and security relations with Vietnam in recent years. The US Navy signed a military medical cooperation agreement with its Vietnamese counterpart in August 2011, the first bilateral military cooperation agreement since the normalization of relations between the two countries in 1995. During his visit to Vietnam in May 2016, Obama announced the full removal of the US' 50-year arms sales embargo on Vietnam.

The United States holds CARAT joint military exercises with Malaysia every year and has helped it build a radar station to strengthen monitoring in the South China Sea.

IV US South China Sea interests and policy

The first and most fundamental interest of the US in the South China Sea is to maintain freedom of navigation for its naval vessels.

From the US' perspective, China's large-scale construction activities in the South China Sea confirmed its suspicion that China intended to implement an Anti-Access/Area Denial (A2/AD) strategy, a predetermined premise for the Obama administration to propose and push forward the strategy of rebalancing to the Asia-Pacific. The US has made the South China Sea an important vehicle for it to implement its rebalancing to the Asia-Pacific.

V China-US military exchanges and cooperation

China is devoted to building a new type of major-country relationship with the US that features the principles of "non-conflict, non-confrontation, mutual respect and win-win cooperation". These are also the principles that provide the foundation for its efforts to promote military-to-military relations.

Although frictions and trials of strength between the two militaries in the South and East China seas are on the rise, this does not disrupt their high-level dialogue mechanisms and important exchange programs. Rather, the two militaries have become more open and flexible in their exchanges and cooperation on navigational safety issues as evidenced by 2014's Memorandum of Understanding on the Rules of Behavior for the Safety of Air and Maritime Encounters and the Code for Unplanned Encounters at Sea, the mutual visits of naval vessels, exchanges between military academies, their joint exercises and their dialogue on cyber security.

Given their differences in history, culture, traditions, social system, ideology and level of economic development, it is inevitable that China and the US will have differences and even frictions over some issues. But both China and the US are permanent members of the UN Security Council with extremely important responsibilities for maintaining peace and promoting development in the Asia-Pacific and the world at large. Both countries want to see a peaceful, stable and prosperous Asia-Pacific and the global commons - outer space, cyberspace and the high seas, including the East and South China seas. Therefore, the two countries need to always keep the whole picture in mind, stick to the overall objective of building a new type of major-country relationship, and recognize that their shared interests far outweigh their differences. The two also need to reduce frictions and manage any crises in a timely way, and stay committed to increasing understanding and building more consensus through dialogue and consultation in a constructive way.