NATO has worries more pressing than Donald Trump. It needs a new role in a changed world.

President Donald Trump has become an unlikely defender of NATO. Last week, he excoriated French President Emmanuel Macron for telling The Economist that the Atlantic alliance was in a state of “brain death.” It was an uncomfortable look for Trump, who usually finds himself in the role of NATO antagonist — attacking NATO allies for free-riding and not taking their own security seriously.

But Macron is right. NATO’s fundamental problem is that the military alliance no longer reflects a common strategic reality. Created to counter a threat that no longer exists, the alliance’s widening fissures are becoming impossible to ignore.

When NATO was created in 1949, Europe lay shattered by World War II. America was demobilizing and disarming while the Soviet Union, despite suffering devastating losses in its war against Germany, menaced Europe with an enormous army and a sizable fifth column. NATO was a necessary, united and limited military alliance of just 12 members.

In confronting the real threat of Soviet conventional and nuclear power through collective defense, it embodied the famous words of one of America’s Founding Fathers, Benjamin Franklin, in 1776: “We must all hang together, or most assuredly we shall all hang separately.”

Russia is not the Soviet Union

Today, three decades after the fall of the Berlin Wall, that is no longer true. Russia inherited most of the USSR’s territory and arsenal, but Russia is not the Soviet Union. Even using purchasing power parity, its economy roughly equals Germany’s. The European Union’s population is more than triple Russia’s. The combined defense spending of just three of NATO members — France, Germany and the United Kingdom — equals Russia’s military outlays. Though Russia can and does fight in its near abroad, those campaigns in Georgia, Ukraine and Syria have largely demonstrated the limits of Russian power.

The Western European NATO heavyweights know they have little to fear from Russia, and they are starting to say so. Macron has openly stated that the real threats to Europe are terrorism and mass migration, threats that NATO has no answer for.

As U.S. politicians are finally trying to wind down the intractable war on terror in favor of renewed great power competition with Russia and China, Macron seeks to lead NATO the other way.

Elsewhere in the alliance, the picture is more muddled. The newer Eastern European NATO members fear Russia — though President Vladimir Putin is highly unlikely to invade the Baltic states, let alone Poland.

German Chancellor Angela Merkel is far more cautious in her rhetoric than Macron, but Germany’s paltry defense spending speaks louder than words. Germany, the world’s biggest importer of natural gas, is forging ahead with the Nord Stream 2 pipeline, further increasing its dependence on Russian natural gas.

Turkey has ignored NATO and purchased Russia’s S-400 air defense system — another problem to which NATO has no solution.

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NATO members are further divided on the most important question: Would they fight to defend an ally against Russia? A 2015 Pew Research Center poll of NATO member citizens, conducted during mounting tensions at the height of the Ukraine war, found Europeans were split on honoring collective defense. Majorities in France, Germany and Italy opposed using military force against Russia. Only in America and Canada did a majority of the public think their country should fight Russia on behalf of a NATO ally.

On the other hand, NATO member citizens fully expect the United States to fight Russia on their behalf.

What about China and NATO?

If not Russia, then China? America’s national security establishment has belatedly reoriented itself on China, but the pivot is now undeniable and probably irreversible. There is no such sea change in Europe.

France, Germany and likely even the United Kingdom will allow Huawei to participate in their 5G rollouts, a situation that is concerning to their own spies. Yet Macron is probably speaking for the continent when he says it's not NATO’s purpose to designate China (or Russia) as “enemies.”

Even were NATO to be united against China, the past 30 years have shown us that the alliance is severely limited in both will and skill when it attempts “out of area” operations.

The Libyan war in 2011, though right on Europe’s doorstep, was a fiasco in both conception and execution. Only eight of 28 members chose to participate in combat, and most of them ran out of either ammunition or spare parts in the course of bombing one of the worst militaries in the world. When Moammar Gadhafi was overthrown, NATO members had no appetite for actually stabilizing Libya. The result has been chaos and Libya’s rapid collapse from Africa’s wealthiest country to a failed state.

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Afghanistan was in some ways worse. Though the collective defense Article 5 was invoked and NATO was united against al-Qaida and the Taliban, the alliance’s appetite for actual fighting was largely absent. Though some countries such as Britain, Canada and Denmark proved the exception, most NATO forces in Afghanistan were fundamentally risk averse, a posture expressed in national “caveats” that hamstrung operations. Some U.S. soldiers darkly joked that ISAF — NATO’s International Security Assistance Force — actually stood for “I saw Americans fighting.”

NATO is not adrift because of nasty rhetoric. Neither Trump’s transactional bullying nor Macron’s barbs are the cause of NATO’s ennui. The Atlantic alliance is marshaling armies that can’t fight for countries that won’t, against a secondary threat. Neither Trump nor Macron is the real threat to NATO. Reality is.

Gil Barndollar, the Military Fellow-in-Residence at the Catholic University of America’s Center for the Study of Statesmanship, is a senior fellow with Defense Priorities. He served as a Marine infantry officer from 2009 to 2016.

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This article originally appeared on USA TODAY: Trump isn't NATO's big problem, it needs a new role in a changed world