By adopting Mr. Putin’s Newspeak we aren’t offering him a useful diplomatic fig leaf. We are convincing him of his strength and our weakness. When Russian troops fighting in Ukraine are described on Russian state television as being “on vacation,” the Kremlin is asserting not only that it can send soldiers to Ukraine, but that it can explain their presence with an aggressively transparent excuse that amounts to thuggish mockery.

Mr. Putin is challenging us with a double bluff, one military and one rhetorical. Reasonable people can differ on how much we should be supporting Ukraine and on how strongly we should be sanctioning Russia. But it is no longer possible to disagree about what is happening.

This is not a civil war, nor is it a fascist coup. Eastern Ukrainians are not rising up against an oppressive regime in Kiev.

We don’t know whether this week’s talk of cease-fire is real or just a feint, nor do we know if Ukraine will survive as a viable, independent country. But one thing is already certain: Russia has invaded a sovereign, democratic state, and through that use of force aims to shape its actions.

We may decide we lack the will to stop this or to more forcefully help Ukrainians to stop it, but in making that decision we need to be clear about what is going on. The distinction between lies and truth matters here because this conflict started with the Ukrainian people’s revolt against authoritarianism and in favor of the liberal rights and responsibilities Ukrainians call European values. This is partly a fight of freedom of speech against censorship. In the Ukrainian-Russian conflict, moral clarity is essential, but to get there we need linguistic clarity, too: Ukrainians decided to build a democracy at home and to make a trade deal with Europe; Russia invaded.

As the Lithuanian president, Dalia Grybauskaite, put it earlier this week (on Twitter, of course), “#Ukraine is attacked because of its European choice. It is not only defending its territory, but also #Europe and its values.”

If the fighting in the Donbass was in fact a civil war, it would matter to Ukrainians, Russians, Eastern Europeans and everyone who cares about the thousands who have died. But the wider security implications would be limited. Countries do break up — the Soviet Union, Yugoslavia, Czechoslovakia, perhaps even the United Kingdom.