Once again Donald Trump has shocked the foreign policy establishment. He suggested that maybe the U.S. should no longer defend its prosperous, populous allies in Europe.

The North Atlantic Treaty Organization made sense when created in 1949. War-ravaged Western Europe faced an aggressive Soviet Union. The American defense shield allowed Washington’s allies to recover and rebuild.

Nearly seven decades later the alliance has become a means rather than an end. The world has changed, yet Washington continues to guarantee the security of its 27 (soon to be 28) NATO allies (as well as Japan, South Korea, and others). Yet only four European nations bother to devote even two percent of GDP to the military, barely half America’s level.

Trump sees this as just a free-riding problem. He said he’d like to keep the alliance, but doesn’t know if it’s possible. “Many NATO nations are not making payments, are not making what they’re supposed to make,” he complained.” He “would prefer not to walk,” but if the Europeans don’t “fulfill their obligations to us,” perhaps Washington shouldn’t defend them.

A predictable firestorm erupted about America keeping its word and reassuring allies. The Trump campaign appeared to retreat ever so slightly: aide Sam Clovis downplayed the candidate’s remarks: “We just want people to follow the rules. We’re putting a marker out there.” Trump told the Washington Post: NATO is a “good thing to have” and “I don’t want to pull it out.”

Alas, Trump fundamentally misperceives the real problem. As I argue on Forbes: “The issue is not burden-sharing, getting the Europeans to do more. It is burden-shedding, turning responsibility over to the Europeans. There no longer is any geopolitical justification for America to defend Europe.”

The only potential serious threat facing Europe is Russia, and even that fear is overblown. Vladimir Putin’s behavior is egregious, but he’s shown no interest in dominating or conquering distant territories peopled by non-ethnic Russians.

In any case, Europe enjoys a population advantage approaching three-to-one and economic lead of nearly ten-to-one over Russia. Europe has a larger population and economy than America. Even today Europe spends two to three times as much as Russia on the military.

Why should the U.S. maintain the status quo?” America gets a lot out of the alliance, argue representatives of the countries being defended. Jens Stoltenberg, the former Norwegian prime minister who now serves as alliance secretary general claimed that “we defend one another,” pointing to European contributions in Afghanistan. But these are far less than America’s role in that nation, and far less costly than bearing most of the burden in confronting nuclear-armed Russia.

The U.S. is interested in the continent’s security and stability, it is said. Of course, but the Europeans have an even greater interest. Yet they lack an incentive to act if America promises to take care of their problems.

Moreover, there’s an even better case for the Europeans to subsidize America’s defense. After all, the continent is vitally interested in U.S. well-being. Why don’t the well-heeled Europeans subsidize American security?

Washington uses bases in Europe for its misbegotten activities in the Middle East, contend some NATO enthusiasts. But America would be much more secure if it didn’t intervene so promiscuously and disastrously. Anyway, it’s possible to negotiate base access without promising to inaugurate nuclear war on behalf of the host country.

As for Trump’s complaints, increasing Europe’s outlays would not suddenly make it in America’s interest to defend that continent. Nor would any increase be sustainable. Most Europeans perceive little threat, and thus little justification, for additional military outlays.

As I observe in Forbes: “No one should mistake Donald Trump as a great strategic thinker. But when it comes to foreign policy he exhibits more common sense than the usual gaggle of establishment politicians, starting with Hillary Clinton. NATO has outlived its usefulness. The U.S. should turn over defense responsibility for Europe to Europe.”