The Eurofighter Typhoon is Germany’s premier front-line jet fighter. This week, Der Spiegel reported that just four of the Luftwaffe’s 128 Typhoons are combat ready. You read that right: four. Also, not one of the German Navy’s six submarines is in a condition to put to sea, and only 95 of its 244 battle tanks are operational. At this point, Luxembourg could probably conquer Germany.

Should anyone seriously care that Germany, with the world’s fourth-largest economy, would be unable to defend itself in the event of war, much less fulfill its treaty obligations to NATO? Not if all you can think about is how Donald Trump is going to squirm out of one potentially incriminating lie by inventing another.

But Vladimir Putin undoubtedly cares, and so does Trump. It’s a toxic combination.

Germany’s persistent, deliberate military weakness is a reminder of just how unprepared much of the world is for the continued unraveling of global order, characterized by two pronounced trends: emboldened dictatorships and risk-averse, inward-looking democracies.

About the former: Bashar al-Assad continues to advance against his opponents in Syria, despite last month’s feckless U.S. missile strikes. The Kremlin reportedly intends to supply Assad with advanced antiaircraft systems to defend against Israeli attacks. Israel is bracing for war with Iran and its militant proxies in Lebanon, even while it is being savaged in the media for defending its border fence with Gaza

Elsewhere, Russia is sitting unmolested on its conquests in Ukraine. Beijing continues to militarize artificial islands in the South China Sea, reportedly by deploying surface-to-air and anti-ship missiles to them. Turkey rolled its tanks into Syria against U.S.-allied Kurdish forces — the ones who have done the bulk of our fighting against ISIS — to little U.S. protest.

Against this stands an American president whose governing foreign policy instincts are bluster and retreat.

In the last month or so, Trump has said he wants to withdraw U.S. troops from Syria that are now the chief deterrent against the Turks, though France’s Emmanuel Macron seems to have persuaded him not to remove them yet. The administration’s trade negotiators are forcing a renegotiation of Nafta that appears to be calculated to invite rejection by legislatures in Mexico or Canada, and maybe the U.S. Congress, too. If they do, Trump could declare the trade pact a dead letter, whether or not that’s legal.

Then there is South Korea. On Thursday, The Times’s Mark Landler reported the stunning but not entirely surprising news that Trump has ordered the Pentagon to prepare options for withdrawing at least some of America’s 28,500 troops from the peninsula.

Why now? Part of the answer is that Trump is trying to force Seoul to foot more of the bill for the U.S. military presence. But Seoul already pays half the U.S. costs and fields one of the largest armies in the world. Unlike Germany, it is no military deadbeat.

A likelier answer is that Trump sees American withdrawal as an achievement in its own right and hopes a peace treaty with the North is his ticket.

This is the kind of classic diplomatic blunder that, had it been committed by a Democratic president, would have produced thunderous denunciations from people like John Bolton and Mike Pompeo. Here’s an administration squeezing a close ally while telegraphing our negotiating terms to a deadly enemy. Expect Pyongyang to demand substantial U.S. withdrawals as its price for promises of peace and denuclearization. Beijing, which has long aimed to push the U.S. out of East Asia, will be thrilled.

The G.O.P. counternarrative is that Trump has cowed Kim with sanctions and military threats. Please: Kim is running the exact same play his father and grandfather did. And the president is simply not a liberal internationalist in the mold of Harry Truman, concerned with the welfare of the free world. He’s a nationalist transactionalist. He believes in what’s-in-it-for-us, specifically what’s-in-it-for-him. This has been his core conviction for at least 30 years, if not his whole life.

Let’s close with some questions for the president’s right-wing supporters.

Does Trump have any larger goal in Korea other than to find a pretext for a military exit and gain a moment of glory along the way?

Does he have a detailed strategy toward Iran other than to renounce the nuclear deal and hope for better terms?

Is the plan for Syria to let Assad — and his Iranian and Russian patrons — win, and let the Israelis and other U.S. allies deal with the fallout?

Is there a concept for a North American trade regime should Nafta collapse?

The world learned on Sept. 1, 1939, where the mentality of every-country-for-itself leads. Our willful and politically wounded president is leading us there again. A warning to countries that have relied too long and lazily on the promises of Pax Americana: The policeman has checked out. You’re on your own again.