U.S. Secretary of State John Kerry travels to Asia this week for talks with Chinese and South Korean officials. But he will not be visiting Japan, which is moving closer to Russia and India amid uncertain relations with Washington.
Japanese paratroopers are training to defend disputed islands in the East China Sea, as China increases naval patrols under a new air defense zone that includes the islands.
It's a standoff that increasingly threatens to involve the United States at a time when relations between Washington and Tokyo are strained over the Yasukuni Shrine, which honors millions of Japanese war dead including 14 convicted of war crimes following World War II.
Prime Minister Shinzo Abe says he went to the shrine to pray for veterans without "hatred or hostility."
The U.S. expressed disappointment and urged Abe to "find constructive ways to deal with sensitive issues of history."
Abe faces domestic political pressures, says American University professor Lou Goodman.
"He has decided, obviously, that he is going to respond to those and not worry about the international implications of that," Goodman said. "That's not good for international relations."
Chinese Foreign Minister Wang Yi says Japan is trying to justify wartime aggression.
"Abe's defense only proved that he is stubbornly sticking to his wrong conception of history that goes against internationally acknowledged truth and justice," Wang said.
Beijing benefits from uncertainty between Tokyo and Washington according to Michael Auslin, director of Japan Studies at the American Enterprise Institute.
"We send a message to other allies that if a 50-year-old alliance can become undone fairly quickly over these issues and the two sides now have taken, certainly on the Washington side, to publicly shaming and criticizing the partner, for example over the Yasukuni issue, that all alliance relations can be similarly upset," Auslin said.
There was no public talk of the shrine controversy from Kerry and Japanese Foreign Minister Fumio Kishida last week. Instead, they focused on economic and military cooperation.
"No matter what, Japan is an important ally of the United States and will continue to be an important ally of the United States for the foreseeable future," Goodman said. "That being said, Japan, of course, is looking for other alliances as well."
Including Russia, where President Vladimir Putin described his country and Japan as natural partners, adding that he and Abe are discussing ways to end their own territorial disputes.
Indian and Japan
Meanwhile, Indian Prime Minister Manmohan Singh is working with Abe on new defense and trade deals, including civilian nuclear energy.
"It's very clear that Japan and India are seeing more commonalities between them and not waiting to see how Washington's going to act," Auslin said. "Now, that can actually be very good both for the region and even for the United States. But it's not good if it's happening because both sides are frustrated and uncertain about the role that the U.S. is going to play."
Kerry begins his trip in South Korea, where Seoul has its own territorial dispute with Tokyo over islands with rich fishing grounds that may also contain large deposits of natural gas.