Be careful what you wish for. U.S. officials have long urged Japan to loosen limits on its military, bear more of the burden of its own defense and play a more prominent global role.
Now, Japanese politicians gearing up for a Dec 16 parliamentary election are promising to do just that - but with a strain of strident nationalism that could give not only Asian neighbors but also Washington cause for concern.
"Who can protect Japan's beautiful seas? Who can protect our territory and our people's lives?" queried former Prime Minister Shinzo Abe, standing before a huge Japanese national flag as he blasted the current government's handling of a territorial row with China in a recent speech.
"The crisis is before our very eyes ... We will take back our country, our nation."
Opinion polls suggest Abe's opposition Liberal Democratic Party (LDP) will win the most seats in parliament's lower house, putting the hawkish lawmaker in pole position to become Japan's seventh prime minister in six years. He abruptly quit the job in 2007, when the LDP was in power, after a troubled year in office.
Parts of Abe's agenda, including calls to drop Japan's self-imposed ban on exercising its right of collective self-defense, or defending an ally under attack, and to boost defense spending after years of decline, would be welcome in Washington.
Abe also wants to revise Japan's U.S.-drafted constitution, never altered since it was adopted after World War Two. U.S. officials have indicated in the past that they would like to see Tokyo loosen constitutional restraints on its military to allow a bigger global security role.
But other aspects, such as an aggressive stance toward China that risks aggravating an already tense territorial row, and a desire to rewrite what conservatives see as overly apologetic accounts of Japan's wartime past, would not only upset China and South Korea but the United States as well.
"The United States has been welcoming, even encouraging nationalist politicians as long as they are keen on reform and that Japan should share more burden in the security arrangement," said Sophia University professor Koichi Nakano.
"But maybe they are beginning to realize that the Japanese right is going too far and setting Japan on a collision course with China that might require American involvement."
Abe, a 58-year-old political blue-blood, is hardly alone in his hawkish stance.
Popular Osaka Mayor Toru Hashimoto's Japan Restoration Party, officially headed by former Tokyo Gov Shintaro Ishihara, an outspoken nationalist and China critic, comes in second in some recent opinion polls - ahead of Prime Minister Yoshihiko Noda's Democratic Party of Japan (DPJ).
Ishihara sparked the row with China over tiny islands claimed by both countries by floating a plan for the Tokyo Metropolitan Government to buy them from private owners, which pushed the central government to purchase them instead.
The 80-year-old Ishihara has also called for Japan, the only country to suffer an atomic bombing, to consider nuclear arms.
How far such hawkish rhetoric resonates with ordinary voters in a country that has prided itself on its peaceful path since its defeat in World War Two is hard to gauge.
A Kyodo news agency survey in mid-November put pensions and the economy at the top of voters' election concerns and an analysis of election-related tweets published by the Asahi newspaper showed comments about nuclear power - a key public concern after last year's Fukushima radiation disaster - far outstripped remarks about diplomacy and the constitution.
Still, China's growing assertiveness in maritime feuds is compounding Japanese concerns about its neighbor's rising military and economic clout. Flag-waving and expressions of patriotism are no longer the taboo they once were in Japan.
News that North Korea is planning a long-range missile test this month is also likely to give fresh impetus to calls for Japan to have stronger defenses and could give an election boost to Abe, known for his tough stance toward Pyongyang.
Waseda University Professor Masaru Kohno said his recent Internet surveys show younger Japanese increasingly keen to see the government take a tough stance toward Beijing and Seoul.
"The phenomena (territorial rows) are not entirely new, but the reaction is extraordinary so maybe you have to think the mood of the nation is tied to something like economic conditions or being politically fed up," Kohno said. "It's not like an ideological surge to the right, it's more like frustration."
Some fear that such frustration is translating into a longing for a strong leader, regardless of policy content.
"Fundamentally, the Japanese people are looking for leadership with a clear sense of direction," said a former U.S. diplomat. "Abe's way of addressing this is to project strong views associated with nationalism."
Some pundits and political sources predict Abe, who quickly moved to repair chilly ties with China as premier in 2006, would again tack to the center if he takes office, not least because the LDP will probably need its long-time and more moderate coalition partner, the New Komeito, to form a government.
Others say pressure from Hashimoto's Restoration Party on the right means shifting gears would not be easy.
"There could be cause for concern if the level of rhetoric is sustained and there isn't an effort to deal with things in a practical way in Asia," the former U.S. diplomat said. "At the end of the day, what really counts is after the campaign."© (c) Copyright Thomson Reuters 2012.