Biden Said the U.S. Would Protect Taiwan. But It’s Not That Clear-Cut.

In August, after the American withdrawal from Afghanistan left some allies wondering how much they could rely on American commitments, he told ABC that “we would respond” if there was an action against a NATO ally, adding, “same with Japan, same with South Korea, same with Taiwan.”

In fact, the treaty obligations with NATO, Japan and South Korea are quite different from what they are with Taiwan, or the Republic of China, which Beijing has declared as its territory since it was established in 1949.

But he may be reflecting a desire to toughen Washington’s language to counter new Chinese capabilities, which would allow far more subtle moves to strangle Taiwan — cutting off undersea cables, internet connections and liquid natural gas shipments — than an outright invasion.

And some believe that the era of strategic ambiguity should come to an end — that ambiguity no longer fits the moment. “It’s grown long in the tooth,” said Richard Haass, a former senior State Department and national security official who is now president of the Council on Foreign Relations. “It is time to change from strategic ambiguity to strategic clarity.

Mr. Haass and a number of other experts and former government officials think it would be wiser to make it clear to Beijing exactly what kind of economic penalties would follow any effort to intimidate or take over Taiwan.

That may yet happen whenever Mr. Biden gives his long-delayed China strategy speech, laying out his approach to a country that is a military, economic and technological challenge on a scale the United States has not seen before. But the White House is not ready for any kind of alteration to its policies.

“What should be clear from all his comments on Taiwan,” a State Department official said in a written statement, is that “our support for Taiwan is rock solid and we are committed to peace and stability in the Taiwan Strait.”