Chinese vessels frequently test maritime claims by South Korea and Japan in the northern Pacific. To the south, Beijing carries out frequent large-scale military exercises around Taiwan, which it says will one day be "reunited" with mainland China.
Beijing also claims most of the South China Sea as Chinese territory, despite a 2016 international tribunal rejecting these claims. "China is, of course, the big concern in the region and this appears to be a response to China building out its own capacity," Dan Pinkston, a professor of international relations at the Seoul campus of Troy University and a former US Air Force officer, told DW.