Opinion | This D-Day, Europe Needs to Resolve to Get Its Act Together

Military power: When the Cold War ended in 1990, the West German military fielded more than 500,000 troops and spent 2.5 percent of its G.D.P. on defense. As of last year, it was down to 181,000 troops and 1.57 percent. Britain’s Royal Navy, the most powerful in the world at the outset of World War II, can now deploy just 10 submarines and fewer than two dozen major surface warships, some of which are inactive.

In an all-out war, the British would exhaust their defense capabilities in about two months, according to a report to the House of Commons defense committee. The same would likely be true — if not much sooner — for every E.U. member-state apart from Poland, which aims to spend as much as 5 percent of its G.D.P. on defense next year.

Demographics: What do Chancellor Olaf Scholz of Germany, his predecessor Angela Merkel, President Emmanuel Macron of France, Prime Minister Mark Rutte of the Netherlands and the former British prime minister Theresa May have in common? They are childless. That’s their personal business (and far from representative of all E.U. leaders), but it’s symbolic of a continent where just under 3.9 million Europeans were born in 2022 and 5.15 million died. A shrinking and aging population typically correlates with low economic growth, not least because entrepreneurship is usually a young person’s game.

Europe has an additional challenge: a relatively high Muslim birthrate, along with the prospect of long-term Muslim migration. Under a “medium migration” scenario estimated by Pew, by 2050 Britain will be nearly 17 percent Muslim, France 17.4 percent and Sweden 20.5 percent. Those wondering about the ascendence of far-right European parties, who are heavily favored to sweep this week’s elections in the E.U. Parliament and who are often sympathetic to Vladimir Putin, know this is a factor. And they need to be honest that the values of depressingly notable segments of these Muslim populations are fundamentally at odds with European traditions of moral tolerance and political liberalism.

Purpose and will: Many of Europe’s current failings are explained (often by European leaders themselves) as a problem of political mechanics: insufficient coordination between states; inadequate power in Brussels; failures of transmission between declared goals and real-world results. But the problem isn’t just one of process. It’s also one of spirit. A few questions:

• If Russia defeats Ukraine and decides in a few years’ time to attack one of the Baltic countries, is there a deep pool of young Germans, Belgians or Spaniards willing to die for Tallinn or Vilnius?

• As Europe’s NATO members struggle to meet the bare minimum goal of spending 2 percent of their G.D.P. on defense, are they willing to come to grips with the fact that they probably need to spend twice as much?

• How much state protection, in social welfare and economic regulation, are Europe’s aging voters willing to forgo for the sake of creating a more dynamic economy for a dwindling number of young people?

• How forceful are European leaders willing to be in insisting that their values — including freedom of speech, women’s rights and gay rights — must be protected against the illiberal instincts of a growing share of their voters?

Trump’s ideas about NATO, his zero-sum attitudes about winning, his fondness for strongmen and his ignorance of and indifference to history are all, rightly, causes for European alarm. But people, and nations, succeed or fail to the extent that they refuse to hand over responsibility for their fates to others.