Thousands of North Korean troops are now in Russia, preparing to help Russian dictator Vladimir Putin’s war of conquest in Ukraine. The newly arrived soldiers reportedly come from the Special Operations Force—the most capable part of North Korea’s army—and could be deployed in Russia’s Kursk region, in an effort to take back territory that Ukraine seized in an offensive this past summer. But Western military observers can only guess at how well equipped they are or how well trained they’ll be relative to battle-hardened Ukrainian forces.

What we do know is this: Putin saw an opportunity to improve Russia’s position in the war that he started, and he took it—apparently with little regard to what the West might think.

Counting on the United States to do nothing appears to have been a good bet. On Wednesday, Defense Secretary Lloyd Austin acknowledged what Ukrainian and South Korean intelligence had been saying for some time: that Kim Jong Un’s hermit state had joined forces with Russia. When pressed by reporters about what North Koreans’ role might be, Austin responded, “If they’re co-belligerents—[if] their intention is to participate in this war on Russia’s behalf—that is a very, very serious issue.” He is trying to sound tough, but his comment means nothing.

Since the beginning of the current war, in February 2022, the Biden administration has dithered again and again. Should Ukraine be offered high-tech American weaponry, such as HIMARS rocket equipment, Abrams tanks, ATACMS missiles, F-16 fighters, and even long-range JASSM missiles? (In most of these cases, the U.S. relented and provided the requested equipment, but Ukraine missed valuable opportunities to set back Russia’s war machine.) Would the U.S. allow Ukraine to use Western weaponry to attack Russian-occupied Crimea, the Russian-built Kerch Bridge, or military assets being used to attack Ukraine from just across the border in Russia? Could Ukraine attack military targets deeper in Russia? The U.S. is Ukraine’s most important ally—but it has subjected Kyiv to an endless process in which vital aid has been delayed or denied because the U.S. fears what Putin might think of each step.

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I don’t mean to sound flippant, but the dynamic reminds me of a classic Gary Larson cartoon that shows, in a split screen, a man and a woman lying awake at night in different homes. He is agonizing about what she thinks about him, whether he should call her, whether she even knows he exists. She is thinking simply, “You know, I think I really like vanilla.” The caption reads, “Same planet, different worlds.” Like the man in the cartoon, the U.S. is full of self-doubt and wrestles endlessly with how Russia might feel. The Biden administration has withheld weapons systems at precisely the moments when they would be most useful, thereby allowing Russia to turn this war into a long-term attritional conflict that it did not need to be.

Putin’s thinking about how to conduct the war isn’t complex at all. He regularly and swiftly escalates whenever he believes that doing so will afford him a strategic advantage. He has bombed Ukrainian hospitals and power supplies, plotted sabotage attacks on military facilities in Europe, hit up Iran for large numbers of drones and missiles, and bargained with North Korea for millions and millions of shells—all to help him in his quest for military success.

A major factor in American vacillation is the Biden administration’s fear that if the West helps Ukraine too much, Putin will escalate by using nuclear weapons in Ukraine. But Putin has shown many times that his nuclear threats are hollow. Following through on them would isolate him from his most important ally—China has repeatedly signaled its opposition to the use of nuclear weapons in the conflict—and would not necessarily provide a clear military benefit that would help Russia defeat the Ukrainian army.

He will, however, use any other means to win the war. And the United States, apparently, will keep overthinking—and finding excuses to do nothing. A few weeks ago, Ukrainian and South Korean intelligence started reporting that North Korean forces were getting involved on Russia’s side. Downplaying the importance of Pyongyang’s involvement, American military and intelligence officials initially suggested to The New York Times that the regime had sent engineers to build and operate North Korean military equipment in Russian hands. Subsequently, a video surfaced that seemed to show North Korean troops in Russia being given Russian military equipment. Earlier this week, the British government asserted that North Korean combat troops were on their way to Russia.

Even when the U.S. government finally acknowledged what was happening, its words showed indecision. “What exactly they’re doing will have to be seen,” Austin said.

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That reaction will not deter Putin, who understands that he is in a war, not a negotiation. He appears to doubt the steadfastness of Ukraine’s supporters—and he may be proved right, particularly if U.S. voters return Donald Trump, a Putin admirer, to the White House. The Russian dictator seems intent on bleeding Ukraine to death on the battlefield. Toward that goal, he has tolerated more than 600,000 casualties among his own soldiers, the U.S. estimates. The Russian military under his command has committed innumerable war crimes—against Ukrainians and even its own troops—in pursuit of an advantage. After all this, if Putin believes that using troops from North Korea, a global outcast, will give him an edge, he won’t hesitate to employ them.

Unfortunately for Ukraine, its most important partner isn’t thinking as clearly. We still don’t know, almost three years into the conflict, whether the U.S. wants Ukraine to win or is more concerned that Russia does not collapse. Just a few weeks ago, President Volodymyr Zelensky presented Washington with a considered plan for victory, which involved using longer-range American weaponry to conduct strikes against Russian targets—much as Russia regularly uses Iranian weapons to hit Ukrainian targets.

The Biden administration’s response has been to run out the clock and pass the issue off to its successor. Its excuses have become self-fulfilling: The U.S. has had countless opportunities to step up and help Ukraine promptly, and in every instance, it has prevaricated and wasted time. At some point, Americans should realize that Putin isn’t wondering what the U.S. thinks about him; he is trying relentlessly to win his war. The U.S. should respond to North Korea’s involvement by doing the one thing it always should have done: give Ukraine the means to defeat the Russian invasion.