One way to reinforce this message is for the White House to continue sharing its intelligence on the doings in the Kremlin. Predicting every move Putin made before the invasion has, so far, been an effective strategy. It allowed the world to see the full hypocrisy of his scheme, has strengthened unity in the United States and Europe and is opening eyes in Russia. And it might create a healthy element of paranoia in the Kremlin.European countries dependent on Russian oil and gas, Germany first among them, have to start preparing for a future as independent of Russia as possible. Germany has suspended certification of the Nord Stream 2 natural gas pipeline; the next step must be to rapidly expand facilities for handling liquefied natural gas and alternate sources of energy. This would be a good moment for Mr. Scholz to reopen the case in Germany for nuclear power and for continuing to operate its remaining nuclear power plants.And both Europe and the United States must re-evaluate their relations with China, a far more important economic partner than Russia. A similar breakdown in America’s relationship with China is not inevitable. While significant issues divide the two nations, China’s foreign minister, Wang Yi, spoke publicly recently about the potential for cooperation with the United States on global infrastructure projects. After issuing a 5,000-word declaration of friendship with Russia weeks before the invasion and amplifying Russian misinformation, the Chinese government may now be trying to put some distance between itself and the Russian war of choice.At home, the Biden administration should stop reassuring the American public that our nation will pay little to no cost for this conflict. For one, while it is clear that Mr. Putin’s current aim is to take over all of Ukraine, his erratic behavior makes it impossible to predict his next move. If he took military action against Poland or the Baltic States, the United States would have to honor its pledge to defend its NATO allies.More immediately, while the U.S. government is right to combat inflation and a rapid rise in prices, the administration’s duty is to warn that standing up to Mr. Putin may well contribute to higher prices and that Americans should be prepared to accept a measure of sacrifice as part of the free, democratic, interconnected world. It is not too late to sound that call.In the near term, the need to support Ukraine — short of putting Western boots on the ground there — is obvious, and much of the world has responded. But one week after the invasion began, Russian forces had seized the strategic port city of Kherson in the south; a roughly 40-mile line of military vehicles stood poised to move on Kyiv, the Ukrainian capital; and Russian forces were encircling the northeastern city of Kharkiv. More than a million Ukrainians have already crossed Ukraine’s borders, creating an epic humanitarian challenge. Many more may be displaced internally.