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