Washington ? China and the United States have largely kept the promise they made 31 years ago not to talk seriously to each other about Taiwan. But leadership changes in Beijing and the Bush administration’s firm commitment to Taiwan may make this the ideal moment to end the nondialogue.

That will sound paradoxical after the flurry created here last week among conservatives and liberals alike by President Bush’s indirect rebuke to Taiwan for proposing a referendum that affects the island’s relations with the mainland. But not for the first time in this town, things may not be what they immediately seem.

More important for the future than Bush’s verbal shot across Taiwan’s bow was the soft handling of Taiwan by Chinese Premier Wen Jiabao, both in his talks with Bush and in the elaborately choreographed public appearances that now showcase Chinese leaders visiting Washington.

Wen steadfastly insisted that China wants peaceful reunification with Taiwan. This may have been for rhetorical effect only. But his carefully chosen words left many of his listeners with the sense that Taiwan has slipped down the list of flashpoints between Washington and Beijing — so far down that a serious political dialogue on the island’s future may no longer be the taboo it became when the two nations signed the Shanghai Communique in 1972.

“The liberation of Taiwan is China’s internal affair in which no other country has the right to interfere,” the Chinese insisted in their section of that bifurcated document. “Countries want independence, nations want liberation and the people want revolution — this has become the irresistible trend of history,” Richard Nixon’s hosts added in the visit-ending statement.

Rereading the communique, in which the United States agreed not to challenge the conflicting claims of Beijing or Taipei to represent the Chinese people, constitutes an exercise in time travel. Both sides fiercely and at length defended their version of the Vietnam War. Economic engagement figured as an afterthought.

Since then, China has attracted $500 billion in foreign direct investment and launched a serious effort to become the manufacturing hub of the world. Taiwan provided $37 billion of that investment, Wen made a point of acknowledging at a dinner sponsored by U.S. corporations and public policy organizations here last Tuesday.

His performance was buoyant and smooth. It was light-years from the defensive and bullying attitude struck on similar occasions by Jiang Zemin, who made regaining Taiwan his personal (unrealized) goal before retiring as president this year. Wen also eclipsed the careful, controlled appearance of Jiang’s successor, President Hu Jintao, who read from a prepared text when questioned about Taiwan at a similar dinner last year.

Hu and Wen do not have the blood of the 1989 repression of the peaceful demonstrations in Tiananmen Square on their hands. They have made clear that “the aim of Chinese foreign policy now is to build a long-term peaceful environment for China’s economic development,” as one senior Chinese official puts it.

There is a window of opportunity for the United States to test the new leadership’s trade-centered commitment to regional and global stability. Cooperation on restricting the spread of nuclear arsenals is the top item on the Sino-American agenda. But there is also room for a reasoned, triangular discussion of how a democratic Taiwan can not only coexist with the mainland, but help in its economic and political transformation.

That is why I think there was less than meets the eye to Bush’s caution to Taiwanese President Chen Shui-bian, who has sought to gain votes in a tight re-election campaign by scheduling a symbolic referendum on March 20 demanding that China withdraw missiles it has targeted on Taiwan.

Bush began his presidency by confronting China’s old guard leadership and stepping up arms shipments to Taiwan. His warning to Chen on Tuesday not to make unilateral changes in the status quo — an articulation of the ethos of the Shanghai Communique — is a minor balancing move that is far less important than the weapons that continue to flow to Taiwan.

Chen can use Bush’s remarks as a face-saving way to cancel a misguided campaign gimmick. Or he can show independence and courage by fighting them. Either way, Bush has done him a political favor, while giving Beijing’s new leaders room to show their true intentions.