Then came September 11, which like Pearl Harbor and the onset of the Cold War, led the right to embrace foreign wars. Now Donald Trump, exploiting grassroots conservative disillusionment with the wars in Afghanistan and Iraq, has revived the anti-interventionist tradition of Coolidge, Harding, and Buchanan. And Carlson is championing it on television.

There’s only one problem. In addition to being a critic of GOP hawkishness, Carlson is also an apologist for Donald Trump on the Russia scandal. On Tuesday, before his showdown with Ralph Peters, he called the furor over Donald Trump Jr.’s willingness to accept anti-Clinton information from the Russian government a “new level of hysteria.” Trump Jr., he insisted, had merely been “gossiping with foreigners.” If that “now qualifies as treason … you ought to think about that before you allow an exchange student to live in your house.”

Carlson’s attempts to dismiss the Trump-Russia scandal aren’t just absurd. (Helping a foreign government subvert an American election isn’t merely “gossiping with foreigners.”) They also undermine his perspective on foreign policy. In his interview with Peters, Carlson said it’s “hard to see why” Putin is “a threat to us.” He told Boot that “the idea that Russia is in the top five” threats to America “is absurd.” A couple of years ago, when America’s primary skirmishes with Moscow were over Ukraine, Syria, and missile defense in Eastern Europe, Carlson might have had a point. Back then, it was plausible to see Russia as a declining power, eager to restore a sliver of its former glory but too weak to seriously threaten America’s NATO allies in Eastern Europe, let alone Western Europe or the American homeland. Back then, China and jihadist terrorism looked like the greater threats.

But 2016 changed all that, because Putin actually did threaten the American homeland. He did it through political subversion, not military attack, but the consequences were almost as grave. By orchestrating a campaign to help Trump through fake news and email leaks, Putin undermined Americans’ right to choose their own leaders. He contributed to the election of a man who is morally and intellectually unfit to be president, and is seriously weakening America’s position in the world. And there’s no reason to believe that Russia will stop. In 2016, it appears, it tried to tamper with voter registration systems. Imagine if, in 2018 or 2020, Russia succeeds, and profoundly undermines the legitimacy of America’s electoral system? That constitutes a far greater threat to the United States than anything ISIS appears able to do.

When it comes to Russia, America’s overriding interest lies in ensuring that Putin doesn’t threaten our democracy. By comparison, Syria is an afterthought. Carlson’s argument about the need for priorities is important. But his defense of Trump wildly distorts his understanding of what those priorities should be. The number one goal in American foreign policy today should be to deter Russia from attacking America’s next election. It’s worth sacrificing cooperation on everything else to achieve that goal. If that undermines the fight against ISIS, so be it. If it undermines efforts to limit North Korea’s nuclear weapons program, so be it. Walter Lippmann famously called foreign policy “the shield of the republic.” And today, the greatest foreign threat to the American republic—to America’s system of government—is Russia’s election attacks. It’s not close.

Tucker Carlson can be a provocative, necessary voice on foreign policy. Or he can be an apologist for Donald Trump. He can’t be both.

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