The expression off-ramp has a pleasing physicality, evoking a thing that can be constructed out of concrete and steel. But at the moment, anyone talking about an off-ramp in Ukraine—and many people are doing so, in governments, on radio stations, in a million private arguments—is using the term metaphorically, referring to a deal that could persuade Vladimir Putin to halt his invasion. Some believe that such an off-ramp could easily be built if only diplomats were willing to make the effort, or if only the White House weren’t so bellicose. It’s a nice idea. Unfortunately, the assumptions that underlie that belief are wrong.

The first assumption is that Russia’s president wants to end the war, that he needs an off-ramp, and that he is actually searching for a way to save face and to avoid, in French President Emmanuel Macron’s words, further “humiliation.” It is true that Putin’s army has performed badly, that Russian troops unexpectedly retreated from northern Ukraine, and that they have, at least temporarily, given up the idea of destroying the Ukrainian state. They suffered far greater casualties than anyone expected, lost impressive quantities of equipment, and demonstrated more logistical incompetence than most experts thought possible. But they have now regrouped in eastern and southern Ukraine, where their goals remain audacious: They seek to wear down Ukrainian troops, wear out Ukraine’s international partners, and exhaust the Ukrainian economy, which may already have contracted by as much as half.

Buoyed by oil and gas revenues, the Russian economy is experiencing a much less severe recession than Ukraine. Unconcerned by public opinion, the Russian army seems not to care how many of its soldiers die. For all of those reasons, Putin may well believe that a long-term war of attrition is his to win, not just in southern and eastern Ukraine but eventually in Kyiv and beyond. Certainly that’s what Kremlin propagandists are still telling the Russian people. On state television, the Russian army is triumphant, Russian soldiers are protecting civilians, and only Ukrainians commit atrocities. With a few minor exceptions, no one has prepared the Russian public to expect anything except total victory.

The second assumption made by those advocating off-ramps is that Russia, even if it were to begin negotiating, would stick to the agreements it signed. Even an ordinary cease-fire has to involve concessions on both sides, and anything more substantive would require a longer list of pledges and promises. But brazen dishonesty is now a normal part of Russian foreign policy as well as domestic propaganda. In the run-up to the war, senior Russian officials repeatedly denied that they intended to invade Ukraine, Russian state television mocked the Western warnings of invasion as “hysterical,” and Putin personally promised the French president that no war was coming. None of that was true. No future promises made by the Russian state, so long as it is controlled by Putin, can be believed either.