As President Biden tries to prevent a Russian attack on Ukraine, his administration continues to wrestle with a world that has refused to conform to its expectations. Russia is not parked. Iran is not cooperating. China—whose activities around Taiwan, as Defense Secretary Lloyd Austin warned last week, look “like rehearsals” for more-serious aggression—has neither engaged with the Biden administration on common issues like climate nor been impressed by Washington’s get-tough policy.

Driving Vladimir Putin’s military buildup...

President Biden and Russian President Vladimir Putin

Photo: mandel ngan/Agence France-Presse/Getty Images

As President Biden tries to prevent a Russian attack on Ukraine, his administration continues to wrestle with a world that has refused to conform to its expectations. Russia is not parked. Iran is not cooperating. China—whose activities around Taiwan, as Defense Secretary Lloyd Austin warned last week, look “like rehearsals” for more-serious aggression—has neither engaged with the Biden administration on common issues like climate nor been impressed by Washington’s get-tough policy.

Driving Vladimir Putin’s military buildup is the Kremlin’s conviction that time is not on its side. Largely because of Ukrainian bitterness at Mr. Putin’s 2014 invasion and the continuing war in the country’s southeastern region known as the Donbass, more Ukrainians are determined to escape what they see as Moscow’s suffocating embrace. Gradual changes in the civil service, the judiciary, the intelligence services and the educational system, implemented with Western encouragement and help, are quietly but steadily pushing Ukraine away from post-Soviet Russia and anchoring it more firmly in the West.

For Mr. Putin and the Russian nationalists whose support he needs, the consolidation of genuine Ukrainian independence is a threat. Russia needs Ukraine, they believe, to dominate the Black Sea, re-establish itself as the principal power in Europe, and defend the Orthodox and Slavic character of the Russian Federation itself at a time of rapid demographic change. A Ukraine aligned with the West, and especially with anti-Russian countries like Poland and the Baltic republics, is an unbearable humiliation and an unacceptable threat to Russian power.

The world has seen this movie before. In February 2014, Ukraine’s pro-Russia President Victor Yanukovych was overthrown after rejecting an economic association agreement with the European Union and opting for closer economic ties with Russia. His successors signed economic and political agreements with the EU, and the post-revolution constitution commits Ukraine to seek EU membership. The West celebrated the 2014 Euromaidan Revolution as a victory for freedom; in retaliation Mr. Putin seized Crimea and invaded the Donbass.

Mr. Putin’s new bellicosity is an admission of Russian failure. Sweet talk about Russo-Ukrainian brotherhood has failed to persuade Ukraine to throw in its lot with Moscow. All that is left is economic pressure and military force. Yet if the political situation inside Ukraine alarms Mr. Putin, the West’s disarray and ineptitude give him hope. In 2014 the West contented itself with economic sanctions and stern lectures when Mr. Putin annexed Crimea and launched an ugly war in the Donbass. America looks weaker and Europe more divided today than in 2014. Mr. Putin likely believes that fumbling Western leaders will be no more capable of stopping Russian aggression now than at any time since his 2008 invasion of Georgia.

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President Biden, scheduled to have a video call with the Russian leader as this column goes to press, seems committed to a so-called peaceful-measures-only approach. Secretary of State Antony Blinken warned of “high-impact sanctions,” and other administration officials have spoken of increased military aid to Ukraine. This sounds robust, but one of Mr. Putin’s favorite diplomatic strategies is to tempt American officials into pompous declarations and then humiliate them by exposing the hollow nature of their pretentious rhetoric. He ran this play repeatedly against the Obama administration, most spectacularly when President Obama told the United Nations General Assembly that Bashar al-Assad must leave power in Syria and Mr. Putin rallied to Mr. Assad’s defense, significantly undermining American power and prestige. He would like nothing better than to fillet Team Biden with the same knife.

Mr. Biden needs to reach a clear decision. If he is committed to helping Ukraine integrate with the West, he will have to convince Mr. Putin that he means business, possibly leading to the dispatch of significant NATO forces to the country. If he does not think Ukraine is worth the risk of a Cold War-style crisis with Russia, he must seek the most dignified retreat Mr. Putin will allow.

Neither course is attractive. Taking a hard line brings the risk of escalation. Many Americans will oppose another open-ended commitment, and Russian enmity for the U.S. will intensify.

Coming so soon after the Afghan meltdown and at a time when many longtime allies doubt America’s word, retreat would be even worse. Russia would become more powerful and more contemptuous of the U.S., while Iran and China will view Mr. Biden as a loser and adjust their policies accordingly.

From a position of strength, the U.S. can and should offer Russia face-saving ways out of the crisis, but on substance Mr. Biden should stand firm. The reality is that Russia has lost its battle for the heart of Ukraine. After encouraging Ukraine to cast its lot with the West for three decades, America’s only honorable course is to sustain Kyiv in this hour of trial.

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