The leader of Britain's opposition Labour Party, Jeremy Corbyn, speaks at Newcastle University, Newcastle Upon Tyne, Britain, on March 17. (Scott Heppell/Reuters)
Deputy Editorial Page Editor

Why have Britain and its NATO allies been unable to deter Vladi­mir Putin from acts like spreading deadly nerve agent in a peaceful British city? Ask Jeremy Corbyn.

When confronted with his government’s conclusion that Russia was responsible for what amounted to a military attack on his country, the opposition Labour Party leader and his spokesman (a) refused to accept that the Kremlin was responsible, (b) cast doubt on British intelligence, (c) complained that Moscow had not been accorded due process and (d) said the right response was “robust dialogue.” In other words, Corbyn echoed almost exactly the line advanced by Putin’s own propagandists.

Then there was President Trump. After Prime Minister Theresa May first pinned responsibility for the attack on Russia, Trump suggested it was still necessary to “get the facts straight” before accusing “whoever it may be.” A day later, when May laid out the case against Moscow and asked for international support, Trump gave a speech in which he condemned a long list of U.S. allies, including Canada, Mexico, South Korea and Japan. But he uttered not a word about the use of chemical weapons against America’s closest ally. Not until Thursday was he ready to concede that it “looks like the Russians were behind it,” even as his own administration issued a much more definitive statement.

Putin launches ventures that even the Soviet Union never dared to try — like the Russian force equipped with artillery and tanks that attacked U.S. troops in Syria — because he can count on de facto allies to weaken or obstruct any response. He has Trump in Washington and Corbyn in London; the latter, London bookmakers say, has roughly a 1 in 5 chance of becoming the next British prime minister.

Hungary’s prime minister and the president of the Czech Republic, both NATO members, already lean Putin’s way, as do two of the top finishers in Italy’s recent election. Russia’s Western corner can be counted on to argue that sanctions are counterproductive, that the West itself is to blame for “creating tensions” with Putin and that the right course is more “robust dialogue.”

Of course, Putin has absorbed some punishment for his invasion and annexation of Crimea, continuing attack on eastern Ukraine, cyber-assaults on the United States, British, French and German political systems, and war crimes in Syria. But the sanctions, including those announced by May and by the U.S. treasury last week, have been modest and conventional. Some spies under diplomatic cover have been expelled; a few companies and oligarchs directly involved in the Ukraine aggression or cyberattacks have been banned from Western travel or banks.

What hasn’t happened, for the most part, are well-plotted financial, cyber and military steps that could seriously threaten Putin. It’s not that none exist. It’s that divided Western governments have been unable to agree on them. “We have tools and could use them,” says former U.S. ambassador Daniel Fried, whose last job was overseeing the State Department’s sanctions shop. “But the British cannot lead, and, though this may change, Trump chooses not to.”

May’s government is indeed handicapped by its impending departure from the European Union, which has isolated it. But there is much more her government could do, if it chose. There are billions of dollars of Russian money laundered into London real estate — a good part of it connected to Putin’s circle. Senior Russian officials send their children to English private schools. Russian companies and banks raise money in London markets.

May was vague about targeting that money in her speech to Parliament. It was hard not to be reminded of what might have been Corbyn’s only legitimate point: Russian oligarchs, he claimed, have contributed more than $1.1 million to the ruling Conservative Party.

The Trump administration’s new sanctions targeted two dozen or so officials and companies that were involved in Putin’s cyberwarfare. But a few had already been listed before. Most of the big oligarchs who hold Putin’s wealth for him and prop up his regime remain immune. In response to congressional legislation passed over Trump’s loud objections, the administration produced a list in January of 210 senior officials and oligarchs close to Putin. Yet no action was taken against them. Treasury Secretary Steven Mnuchin promised Congress on Jan. 30 that “there will be sanctions that come out of this report.” So far, it hasn’t happened.

Fried says the way to deter Putin is to work that “Kremlin list.” We should, he says, “choke off flows of dark Russian money to London, Miami, New York and elsewhere in the West, and let Putin know that we are able to target him.” More weapons for Ukrainians and Syrians fighting Russian forces would also help, as would reciprocal cyberattacks. First, however, comes the hard part: surmounting the opposition of Putin’s transatlantic alliance.

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