America is not going to fight Russia over Ukraine.

"The idea that the United States is going to unilaterally use force to confront Russia invading Ukraine is not in the cards," said Biden. "We have a moral obligation and a legal obligation to our NATO allies," but "that obligation does not extend to … Ukraine."

Anti-interventionists who have opposed bringing Ukraine into NATO may just have kept America out of a confrontation or war with Russia.

Yet hard negotiations lie ahead on the two demands Putin has made a condition of keeping his 100,000 troops on his side of the border.

First, there must be legal guarantees Ukraine will not be brought into NATO. Second, the U.S. and NATO must not arm Kyiv with offensive weapons that would present an intolerable threat to Russia.

Meeting these conditions would seem an easier proposition than getting them written into an agreement acceptable to Kyiv.

How, for example, does Biden get the Ukrainians to accept a U.S.-Russia deal that says their country can never be a member of NATO?

Russian military pressure on Ukraine, however, is but one of several crises where America finds itself at the center.

Biden this week ordered a diplomatic boycott of the Winter Olympics in China. U.S. athletes may participate in the games, but no U.S. government official will attend in a formal capacity.

The White House says the purpose is to show disapproval of Beijing's "genocide" against the Uyghurs, its crushing of the democracy movement in Hong Kong and its threat to take over Taiwan.

Beijing has been contemptuous of the U.S. diplomatic boycott, but Canada, Australia and the U.K. followed America's lead and declared their own diplomatic boycotts.

The Winter Olympics will take place on the 50th anniversary of President Richard Nixon's historic trip, where the U.S., in the Shanghai Communique, acceded to the contention of Chairman Mao Zedong's People's Republic that Taiwan "is a part of China."