Washington has been pressing Tokyo to return 331 tons of mostly weapons-grade plutonium given to Japan during the Cold War era, Japanese and U.S. government sources said in late January.

The Obama administration is afraid that the nuclear material might fall into terrorist hands and is keen to ensure nuclear safety, so it wants Japan to return the plutonium supplied for use as nuclear fuel in a fast, critical assembly in Tokai, Ibaraki Prefecture.

The highly concentrated plutonium could be used to make 40 to 50 nuclear weapons.

Japan strongly resisted returning the plutonium at first, claiming it is needed for researching fast reactors, but it has finally given in to repeated U.S. demands.

Why did the United States move the plutonium to Japan in the first place? Sources say the Three-Mile Island nuclear incident of March 1979, the most serious nuclear disaster in U.S. history, caused deep fear among the population. It was under popular pressure that Washington decided to move the nuclear material to Japan under an agreement signed between the two countries on the civilian use of nuclear energy.

According to the Japan Times, Washington is still haunted, not by the first nuclear test by North Korea in 2006, but by an internal report compiled by the Japanese government on "the possibility of domestically producing nuclear weapons."

Two days after the third nuclear test carried out by North Korea on Feb. 12, 2013, U.S. President Barack Obama called Japanese Prime Minister Shinzo Abe about America's commitment to defend Japan with its nuclear umbrella. Obama was not only re-affirming the Japan-U.S. Security Treaty, but also discouraging Japan from developing its own nuclear weapons.

On May 1, 2013, The Wall Street Journal published an article, saying Japan's nuclear plan unsettles the United States, as Japan was preparing to start up a massive nuclear-fuel reprocessing plant, defying the objections of the Obama administration. The Rokkasho reprocessing facility, based in Japan's northern Aomori Prefecture, is capable of producing nine tons of weapons-grade plutonium annually, enough to build as many as 2,000 bombs.

Japan's plan is a real worry for Washington, as Japanese officials do not hide their nuclear ambitions. Shintaro Inshihara, the notorious former Tokyo governor, and the late former Finance Minister Shoichi Nakagawa openly argued that Japan should have nuclear weapons. Opinions favoring nuclear armament had also been expressed, officially and unofficially, by former prime ministers Nobusuke Kishi (Shinzo Abe's maternal grandfather and prime minister from 1957 to 1960), Hayato Ikeda (1960-64), Esaku Sato (1964-72), Yasuo Fukuda (2007-08) and Taro Aso (2008-2009).

Equipped with advanced nuclear technology, Japan can easily produce hundreds, even thousands of nuclear weapons in a short time. But that would be in violation of its constitution and its obligations as a signatory to the Nuclear Nonproliferation Treaty as well as the Three Principles of a Nuclear Free Japan.

More seriously, it would upset the military balance in strategic northeast Asia, threatening not only Japan's neighbors China and North Korea, but also its ally, the United States.

Recently mutual recriminations between the United States and Japan have been notably on the rise. U.S. officials and media have been sharply critical of Shinzo Abe's Yasukuni Shrine visit and Japan's dangerously provocative acts such as increasing its arms budget and the creation of a national security council and Abe's constant talk of his intention to revise or re-interpret the constitution.

Jackson Diehl, deputy editor of the Washington Post's editorial page, quoted "one informed observer" in a recent article as saying "a communications gap has opened up between Washington and Tokyo more profound that even with Beijing. U.S. officials believe they can no longer be sure of what Abe might do if tensions spike over the islets, or whether he would heed U.S. counsel in a crisis."

It was no accident that Naoki Hyakuta, a newly appointed board member of NHK, declared that the U.S. fire-bombing of Tokyo and the bombing of Hiroshima and Nagasaki were massacres, and that the United States staged the Tokyo trials after Japan's defeat in 1945 to cover up U.S. war crimes.

Shintaro Ishihara never disguised his intention to throw the United States out of Japan.

Japanese nationalists believe that it was the United States that defeated Japan, occupied Japan and wrote Japan's pacific constitution that deprived it of its war fighting rights. Anti-U.S. animosity is deep in the psyche of the Japanese nationalists.

And Washington knows it.

The author is a columnist with China.org.cn. For more information please visit: http://www.jhzsvip.com/opinion/zhaojinglun.htm

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