ON THE ISSUE of China's claim to Taiwan, the Clinton administration, like its predecessors, has pursued a policy of "strategic ambiguity." The United States will provide the increasingly democratic island just enough political and military support to deter China from taking the island by force; but it will not provide so much that Taiwan's leaders feel emboldened to declare independence, which could provoke China to start a war that would almost certainly involve American forces.

This policy grows less tenable as Taiwan gets more and more democratic and China remains a dictatorship. Most Taiwanese understandably don't want to be swallowed by a repressive state, and unlike in the past--when Taiwan was governed by dictators of its own--their views on independence shape national policy. Now China has further weakened the rationale for the U.S. policy of ambiguity. Until now, the United States could fairly argue that Taiwan wasn't suffering much from Chinese threats--and that as long as it refrained from declaring independence, it knew it would be safe. But China has just issued a "white paper" threatening to attack Taiwan not only if it declares independence but also if, in China's judgment, the island's leaders drag their feet in reunification negotiations; and China alone reserves the right to decide how long is too long. This new Chinese rhetoric is preferable to its 1996 firing of nuclear-capable missiles into the sea near Taiwan, prompting the defensive dispatch of two U.S. aircraft carriers. But that's the best you can say for it.

China's new threat, like its 1996 military "exercise," was intended partly to influence a Taiwanese presidential election. It also may have been meant to shore up President Jiang Zemin's flagging status among hard-liners and to underscore China's opposition to the Taiwan Security Enhancement Act, a proposal to increase U.S.-Taiwan military cooperation that has passed the U.S. House.

But the Chinese declaration also provides a window on that country's priorities. It was issued only hours after a high-level U.S. delegation in Beijing finished pleading for restraint on the subject of Taiwan. It could complicate administration efforts to win congressional support for China's entry into the World Trade Organization, as its bullying posture calls into doubt its willingness to live by international rules. None of this deters the regime from making threats.

The administration has in the past bent pretty far to China's wishes. The House was prompted to write the Taiwan bill in part because of President Clinton's public accession, in China, to Beijing's three key demands regarding Taiwan's status. The U.S. response to China's latest challenge should be shaped, at a minimum, by the need not to say or do anything that China could present to the next administration as U.S. acquiescence in its new policy. Strategic ambiguity does, at times, have its uses; this is a moment for strategic clarity.