As NATO allies gather near London this week, existential questions hover in the air above the swanky Grove Hotel: How long will we be around as an alliance? Do we still look united enough to deter aggressors? And can a “European army” spring up to supplement, perhaps even replace, our transatlantic league?

The short answer to that last question is no. Tragically, there won’t be a European army soon, or ever. European leaders should admit that honestly, and all members the North Atlantic Treaty Organization, above all the Americans, should accept that they’d better do their level best to dispel doubts about the alliance. The reality is that, for the foreseeable future, NATO is the only credible military shield Europe has.

The main culprit for this new anxiety is of course U.S. President Donald Trump, whose “transactional” attitude toward NATO has spooked Europeans. He’s right to criticize cheapskates such as Germany for skimping on their military spending. But he’s irresponsible to imply that America’s commitment to Article 5 — which states that an attack against one member state is an attack against all — may be conditional. The main purpose of alliances is deterrence, and that requires unconditional assurances.

A second culprit, if you ask central Europeans, is French President Emmanuel Macron. It was his recent musing about NATO’s “brain death” and the brittleness of Article 5 that caused the current hand-wringing. That’s not because he said something wrong. It’s because, as French president, he shouldn’t have spoken so clearly.

That’s certainly what German Chancellor Angela Merkel seems to feel. She even told Macron that she’s sick of having “to glue together the cups you have broken so that we can then sit down and have a cup of tea together.” Strong tea for a pair that prefers to be seen cuddling.

And yet Merkel, like Macron, is also on record calling for Europeans to wean themselves from the U.S. by creating “a real, true European army.” Those two ideas go together: The only theoretical answer to less American protection is more European self-defense.

That dream is as old as the European project. There were plans for a European army in 1952, drawn up by Belgium, France, Italy, Luxembourg, the Netherlands and West Germany. This was before postwar Germany was allowed to have soldiers again. West Germany’s parliament ratified the idea, but France’s nixed it, which led to the founding of a West German army in 1955, embedded into NATO. European integration followed an economic rather than a military path.

The complications that caused that stillbirth linger. The nations in what is now the European Union still care about their sovereignty, which is expressed above all in the decision to send young soldiers into harm’s way. They also have different interests. The French are busy in their former African colonies. The Poles and Balts feel most threatened by Russia. Germany, caring not a whit about all that, is merrily building itself a second gas pipeline to Russia, circumventing the eastern EU.

Member states also have dissonant historical traditions, which make integration into one command hierarchy almost impossible. Postcolonial France considers military action a legitimate tool of foreign policy, and its president has ample powers to direct its army. Germany, still atoning for World War II, disavows military interventionism. Unlike France, it has a “parliamentary army,” which must get explicit approval from the Bundestag to do anything. Would a French president patiently wait for the German legislature before deciding whether to shoot at little green men speaking Russian in an Estonian forest? Would 27 states cede that decision to Brussels?

The fundamental problem, as Jan Techau of the German Marshall Fund puts it, is distrust: The French and Germans don’t fully trust each other, the Italians trust neither of them, the Germans don’t even trust themselves, Warsaw distrusts Berlin, Bucharest and Budapest distrust each other, people in the Balkans don’t trust anybody, and so forth.

That’s why Macron is seen in central Europe as a neo-Gaullist. When he talks about “strategic autonomy” or “European sovereignty,” he seems mainly to be eager for France, the EU’s only nuclear power after Brexit, to lead Europe, snubbing its nose at the U.S. and accommodating Russia. To advance that vision, he’s sponsored a fledgling alliance called the “European Intervention Initiative,” which is part of neither NATO nor the EU. Needless to say, the EU’s eastern members would much prefer to keep relying on the U.S.

All this helps explain why the EU’s new push for a “defense union” is not actually about integrating armies, but about creating a common market for weapons procurement. How very European. Exhibit A is a European Defense Fund, which will have 13 billion euros ($14.3 billion) to plow into weapons research. Exhibit B is a bureaucracy called PESCO, which aims to coordinate building and buying corvettes, helicopters, drones, and the like across the EU.

A common defense market is a good idea. But confusing markets with might is exactly the sort of pusillanimity that drives Macron crazy, and amuses Russian President Vladimir Putin. The biggest danger is that it might one day also tempt Putin or his ilk to test the West. They wouldn’t need to launch an all-out strike; a good dose of hybrid warfare might suffice to divide Europe. That, at least, is the upshot of scenario games now being played by think tanks. For the sake of peace, let everyone in the Grove Hotel this week remember what’s at stake.

To contact the author of this story: Andreas Kluth at akluth1@bloomberg.net

To contact the editor responsible for this story: Timothy Lavin at tlavin1@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Andreas Kluth is a member of Bloomberg’s editorial board. He was previously editor in chief of Handelsblatt Global and a writer for the Economist.

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