In a six-day span the U.S. State Department has bluntly affirmed unequivocal backing for Japanese territorial claims against both Russia and China, even invoking a defense treaty provision that could lead to direct military intervention and war with the world's most populous nation.
Beginning a 13-day, seven-nation tour of the Asia-Pacific region on October 27 in Hawaii, Secretary of State Hillary Clinton visited Joint Base Pearl Harbor-Hickam and met with Admiral Robert Willard, head of U.S. Pacific Command - the largest overseas regional military command in the world - and held a joint press conference with new Japanese Foreign Minister Seiji Maehara in Honolulu.
Clinton's comments on the occasion underlined Washington's increasingly assertive - and intrusive - role in East Asia and the Western Pacific Ocean. They included:
Responding to a question from the press corps on an East China Sea island chain contested by Japan and China - the Senkaku Islands in the Japanese designation and the Diaoyu Islands in the Chinese - near which a Chinese trawler collided with two Japanese coast guard ships on September 7, almost leading to an international incident, Clinton added that for the government she represents "the Senkakus fall within the scope of Article 5 of the 1960 U.S.-Japan Treaty of Mutual Cooperation and Security. This is part of the larger commitment that the United States has made to Japan's security. We consider the Japanese-U.S. alliance one of the most important alliance partnerships we have anywhere in the world and we are committed to our obligations to protect the Japanese." 
On July 23 Clinton spoke at the 17th Association of Southeast Asian Nations (ASEAN) Regional Forum in Hanoi, Vietnam, and alluding to disputes in the South China Sea between China and ASEAN member states Vietnam, Malaysia, the Philippines and Brunei over the Spratly Islands and between China and Vietnam over the Paracel Islands, she maintained that "The United States, like every nation, has a national interest in freedom of navigation, open access to Asia's maritime commons, and respect for international law in the South China Sea....We oppose the use or threat of force by any claimant."  Clinton had the temerity to evoke the United Nations Convention on the Law of the Sea, which the U.S. has not ratified.
Her allusion to the prospect of force being used is - could only be - a reference to China in the current context. In an indisputable attempt to take up cudgels in alleged defense of the ten members of ASEAN - Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar (Burma) the Philippines, Singapore, Thailand and Vietnam - against what is being promoted by Washington as a common threat, China, Clinton delivered the opening salvo in what has since been an intensifying campaign to introduce the U.S. as not so much a mediator as a power broker and military guarantor in the Asia-Pacific region.
In her comments in the Vietnamese capital on July 23 Clinton foreshadowed the renewed American emphasis on East Asia, in particular on isolating and confronting "outposts of tyranny" (her predecessor Condoleezza Rice's term) Myanmar and North Korea and revivifying and expanding military alliances in the area. 
"The day before, I was in Seoul, my third visit to Korea as Secretary. Together, Secretary Gates and I have sent the strong message that 60 years after the outbreak of the Korean War the U.S.-Korea alliance is strong....I've just completed two days of intensive consultations with my ASEAN colleagues and with the other partners who have come here to pursue a common endeavor: strengthening security, prosperity, and opportunity across Asia....[T]he Obama Administration is committed to broad, deep, and sustained engagement in Asia."