Vladimir Putin’s Ukraine invasion isn’t going according to his script, and for that the world owes a great debt to the heroic people of that besieged country of 41 million. Their resistance against fearsome odds is an inspiration and has awakened the world to the menace of the Kremlin autocrat. Ukraine deserves more support to raise the costs of war for Mr. Putin with arms, the toughest sanctions, and global ostracism.

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Ukraine President Volodymyr Zelensky is proving to be the man for the moment as he rallies his...

President Joe Biden, Russian President Vladimir Putin, and Ukrainian President Volodymyr Zelensky

Photo: Bastiaan Slabbers/NurPhoto/Getty Images; Mikhail Svetlov/Getty Images; Irina Yakovleva/TASS/ZUMA Press

Vladimir Putin’s Ukraine invasion isn’t going according to his script, and for that the world owes a great debt to the heroic people of that besieged country of 41 million. Their resistance against fearsome odds is an inspiration and has awakened the world to the menace of the Kremlin autocrat. Ukraine deserves more support to raise the costs of war for Mr. Putin with arms, the toughest sanctions, and global ostracism.

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Ukraine President Volodymyr Zelensky is proving to be the man for the moment as he rallies his country and the world to resist the invasion. “I need ammunition, not a ride,” Mr. Zelensky said, in a line for the ages, in response to a U.S. offer to help him leave Kyiv to escape a possible assassination.

His leadership has put to shame the New York Times op-ed last week that ran under the headline, “The Comedian-Turned-President Is Seriously in Over His Head.” His pleas on behalf of Europe’s principles have helped to persuade European leaders that Ukraine’s fight is also theirs.

The state of the battlefield is confusing as always in war, but the main news so far is the success of the Ukrainian resistance. Russia still doesn’t appear to control a major city, and on Sunday Ukrainian forces repelled an attempt to take Kharkiv, the second-largest city. This operation was supposed to be a quick Russian march to Kyiv followed by a frightened surrender and the installation of a puppet government. Most Western analysts predicted the same.

They underestimated the tenacity of Ukrainians. The sight on TV and social media of Ukrainian civilians preparing to defend their cities is something to behold. Men with desk jobs are grabbing rifles, and teachers are making Molotov cocktails. This is a lesson in the price of freedom that ought to instruct Westerners offended by “microaggressions.” Real aggression is a tank rolling down your street.

But Ukrainians shouldn’t have to fight urban battles with bombs made in their kitchens, and Europe and the U.S. are finally sending the weapons to Ukrainians that should have been provided long ago. The U.S. is providing some $350 million more in military aid, and the Biden Administration is asking Congress for another $6.4 billion for humanitarian and military assistance. Congress should approve the request this week.

Even the Germans are stepping up, with Chancellor Olaf Scholz saying Berlin will provide 1,000 antitank weapons and 500 Stinger missiles. The Netherlands is chipping in 200 Stingers and 50 Panzerfaust 3 antitank weapons with 400 rockets. Sweden is sending antitank weapons, and many other countries are also contributing.

Former Ukraine Defense Minister Andriy Zagorodnyuk tells us there’s an urgent need for bulletproof vests and helmets. The U.S. can also provide communications gear like tactical radios that will help small groups of Ukrainians carry out operations against Russian troops. As the war continues, the U.S. and NATO will need to develop means of supply from havens in Poland and other border nations. Air drops shouldn’t be ruled out.

Europe, the U.S. and Japan are also strengthening sanctions in a meaningful way. The weekend decision to ban select Russian banks from the Swift financial clearinghouse is a positive step, though it looks like it will still exempt energy transactions. That is an unfortunate bow to the dependence of Western Europe on Russian natural gas. It will diminish the impact of the Swift sanction because energy exports are Mr. Putin’s main financial lifeline.

Much of the world is also increasingly isolating Russia and Russians from travel and commerce. Sports leagues are refusing to compete in Russia, companies are refusing to do business, and Europe and Canada have closed off their airspace to Russian airlines. These may seem like symbolic gestures, but they send a message to the Russian people that their ruler is taking them down a blind alley.

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Despite the good news, Ukraine’s position remains perilous. Russian forces are still besieging several cities, including Kyiv. Mr. Putin is ruthless, as he showed in a Chechnya campaign that reduced cities to rubble. He could do the same in Ukraine if he feels defeat would jeopardize his political control inside Russia.

On Sunday Mr. Putin put his nuclear forces on high alert in response to what he called threatening comments from NATO leaders. But no one is threatening Russia. It’s tempting to dismiss this as more of Mr. Putin’s intimidating talk, except the Russian’s public statements have been erratic and extreme.

The threats shouldn’t stop the growing support for Ukrainian resistance. The stakes of this war are very high, including for American interests. Mr. Putin is trying to restore Greater Russia and make himself the dominant European state and a global power. He wants a new world disorder.

If he succeeds in Ukraine, breaking NATO will be his next ambition. The people of Ukraine are showing a too complacent West what it means to fight for freedom.

Main Street (01/03/22): Critics warn that talk of military action will kill any hope of a diplomatic solution with Iran. But the opposite is closer to the truth. Images: AFP/Getty Images Composite: Mark Kelly The Wall Street Journal Interactive Edition