Real Ukraine peace discussions require a real US security guarantee

By Andreas Kluth  Don’t be distracted by whatever “minerals deal” the US and Ukraine may or may not hash out in the coming weeks, for it will not address the main obstacle to the kind of cease-fire between Russia and Ukraine that US President Donald Trump so badly wants to broker. That question is: How can third-party guarantors credibly assure the security of Ukraine after an armistice? 

Credibility: Every devil in every detail is wrapped up in that one word. The concept is so slippery that it’s kept strategists busy at least since the American scholar Thomas Schelling (who later won a Nobel Prize for his work in game theory) analysed types of deterrence during the early Cold War. We can’t ask Schelling to weigh in on Ukraine today (he died in 2016). But here’s what he wrote about American troops — and obliquely about their British and French partners as well — stationed in West Berlin at the time. 

“What can 7,000 American troops do, or 12,000 Allied troops?,” he asked. “Bluntly, they can die. They can die heroically, dramatically, and in a manner that guarantees that the action cannot stop there. They represent the pride, the honour, and the reputation of the United States government and its armed forces; and they can apparently hold the entire Red Army at bay.” What Schelling was describing is a tripwire force. A literal tripwire is a thread that, when a trespasser stumbles over it, triggers an alarm or a detonation or some other consequence that the intruder has reason to fear. A metaphorical tripwire is a relatively modest deployment of troops that could never stop an invading army but that would, if eliminated by the enemy, compel the home nation to seek revenge and enter the war.

  Deterrence is said to be strong when two conditions are met: First, the country (or coalition) that sent the tripwire force must seem committed to avenging its troops if they are harmed. Second, the country must also be capable of defeating the aggressor, which in the Ukrainian scenario is Russia under its president, Vladimir Putin.

  The Allied tripwire forces in West Berlin and West Germany were an example of successful deterrence: The Cold War, despite several hair-raising crises, never turned hot. Beyond that case, though, precedents of credible tripwire strategies are rare, as Dan Reiter at Emory University and Paul Poast at the University of Chicago have shown.

  In 1949, for example, the Americans kept enough forces in East Asia to deter a North Korean attack on South Korea, but by 1950 the American presence shrank, the tripwire lost credibility, and the North went to war. When the US provides the peacekeepers, the question at least isn’t about theoretical capability — the American military could win any single fight it chooses. Not so when others send the troops.  In today’s Ukrainian context, too, it is moot whether, say, a Franco-British tripwire force without American backing would be either capable or credible in deterring Putin from invading again.

  Now consider why Ukrainian President Volodymyr Zelenskyy is so disheartened by everything Mr Trump and JD Vance have said and done for the past month, during which they’ve taken up the Kremlin’s absurd narrative that Ukraine (rather than Russia) is the aggressor. During the disastrous bust-up in the Oval Office last week, the point the Ukrainian was trying (and failing) to make was precisely this need for security guarantees to be credible, meaning American-backed.

  The security guarantee that Mr Zelenskyy understandably wants, and Mr Putin fears, is Ukraine’s accession to NATO.  Inexplicably for somebody who fancies himself a dealmaker, Mr Trump has already taken that chip off the table before negotiations have even begun. So the European NATO allies and other Western countries are now discussing laying a tripwire without American support. But that runs into the vexed twin question of capability and credibility. No matter what else Trump and others propose, there is no skirting the dilemma: Earnest cease-fire talks cannot begin without the prospect of credible security guarantees; no guarantee can be credible without the US; but the US under Mr Trump is moving away from such a commitment. 

  During the Cold War, American presidents of both parties saw the stakes in hotspots such as West Berlin as nothing less than what Schelling called “the pride, the honour, and the reputation of the United States.” Mr Trump and Mr Vance are quite clear that they define the stakes in Ukraine, which is fighting for its survival as a nation, as little more than the rare earths in its ground. “I’m not worried about security,” Mr Trump snarled at Zelenskyy in the Oval Office. “I’m worried about getting the deal done.” The more Mr Trump says that, the less Mr Zelenskyy can trust, and thus enter, talks to end the war.

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