U.S. Secretary of State John Kerry and Treasury Secretary Jack Lew are in Beijing for talks with their Chinese counterparts on economic and military issues. Washington and Beijing disagree over Japan's military taking a more active role in conflicts outside its borders.
Kerry comes to this Strategic and Economic Dialogue facing Chinese and Korean concerns about a more active Japanese military.
Ending a 1945 ban on fighting abroad, Japanese soldiers will now work more closely with other armies in training and peacekeeping.
Prime Minister Shinzo Abe said he is protecting Japanese citizens. "By being better prepared, it is possible to deter those who look to go to war against Japan," he said.
In Washington, U.S. State Department spokeswoman Jen Psaki welcomed the move. "In order for it to be successful, it Is important they move forward in a transparent manner. But we have an open dialogue with Japan about a range of issues, including our security cooperation and partnerships, and so we expect that to be the case," she stated.
But Chinese President Xi Jinping and Korean President Park Geun-hye say a more active Japanese military could undermine regional stability.
"We demand that Japan earnestly respect the reasonable security concerns of its Asian neighbors. It must not harm China's national sovereignty and security, and it must not damage regional peace," said Chinese Foreign Ministry spokesman Hong Lei.
Yonsei University Professor John Delury said Chinese and Korean opposition to the move complicates U.S. policy in the region. "They will try to find some way to present a sort of a united front against Prime Minister Abe in Japan. And of course, that puts the United States in an awkward position," he said.
Especially as China and Korea each have territorial disputes with Japan. American Enterprise Institute analyst Michael Auslin said it is an opportunity for China. "China has done everything it can to abet a split in Korean-Japanese relations. And I think the two sides, Seoul and Tokyo, are recognizing that you may not like who your neighbor is, but you have got to live with your neighbor, especially when you have got a much more threatening neighbor," he noted.
Korea said it will never allow Japanese forces to affect the Korean Peninsula without its consent, urging Tokyo to pursue its new military posture only within the framework of its alliance with the United States.