Ukraine’s ballyhooed "spring offensive” hasn’t even begun yet, but Western politicians are already using it to reframe their thinking about Kyiv’s defensive war against Russian President Vladimir Putin.

This is a problem. By hyping expectations for the Ukrainians’ imminent military push, the U.S., Europe and NATO may jeopardize Kyiv’s long-term prospects.

The start of the offensive, expected right about now, has been a foregone conclusion since the winter. While the ground was frozen, the Ukrainians and Russians — regular army units as well as mercenaries of the Wagner Group — pinned one another down in a bloody war of attrition with little movement. Meanwhile, the Ukrainians were receiving and being trained to use new weapons, including the heavy battle tanks needed for a counterattack.

Once the earth thawed and the mud receded, the Ukrainians — now properly armed — would then start to take back the regions occupied by the Russians. Ideally, this would mark a turning point leading to a Russian retreat of some sort and ultimately peace negotiations acceptable to Kyiv.

One problem is how the Russians have been using this time. They’ve been ethnically cleansing the Ukrainian territories in their control. They’ve murdered, raped, tortured, jailed and otherwise suppressed those Ukrainians showing resistance, while browbeating the rest into getting Russian passports and doing everything to eradicate Ukrainian culture and replace it with an identity defined by Russian propaganda. Putin’s goal is to ensure that Donetsk, Kherson, Luhansk and Zaporizhzhia — not to mention Crimea — can never become properly Ukrainian again.

Simultaneously, the Russian forces have dug in, with daunting systems and fortifications to defend their positions. Their goal is to repel the expected Ukrainian offensive — or at least limit it.

Political leaders from Washington to Brussels and Berlin, meanwhile, have been doing their best to maintain Western cohesion in helping the Ukrainians in ways diplomatic, economic and military. In this effort, they’ve adopted the coming spring offensive as a preferred rhetorical device.

Some politicians have held out the prospect of a Ukrainian comeback to rally domestic support and counter skeptics. In effect, their pitch is: "Give Kyiv what it needs now and soon the war may be over, so that we can go back to normal.” This is the way the European Union wrangled its 27 members to pledge more ammunition for Ukraine, for example.

A few Cassandras even worry that the spring offensive may turn out too successful. What if Putin’s forces were to collapse in a rout? What if the Ukrainians recapture the four regions he illegally annexed last fall? What if they even retake Crimea? The fear is once again that Putin, feeling cornered and humiliated and dreading his own demise, would then escalate to nuclear strikes.

The danger with both lines — the excessive hope and dread — is that they imply long-term Western support for Kyiv may depend on the coming offensive’s outcome. What if the Ukrainians fail to recapture much territory by summer? Would that mean that all those Leopard 2 and Challenger tanks were in vain? Would it mean the West should deny Kyiv American or European fighter jets in the next round?

And what if the Ukrainians do push all the way to Crimea and Putin rattles his nuclear saber again, or actually unsheathes it? Would the West then back off and abandon Kyiv?

Neither reflex is appropriate — morally, strategically or politically. The reality is, no matter how the Ukrainian offensive pans out, this war is likely to drag on for years. And the West must have Kyiv’s back as long as it takes, no matter the vicissitudes on the battlefield. Too much is at stake — including peace, order and liberty in Europe and beyond.

A related problem in the Western debate is that one side emphasizes only the need to support the Ukrainians in their heroic fight, while the other stresses the imperative of peace negotiations. In the heat of argument, the first increasingly paints the second as calling for Ukrainian capitulation, while the latter caricatures the former as war mongers.

The test of not only a first-rate intelligence, in F. Scott Fitzgerald’s phrase, but also of strategic clarity is to hold two opposed ideas in mind at the same time while retaining the ability to function.

First, the West and all freedom-loving nations of the world must keep supporting Ukraine, no matter how its spring offensive turns out. Second, one day, when both sides are exhausted, there will be peace talks and concessions. Ukraine and the rest of us must simultaneously prepare for both, the fighting and the jaw-jaw.

Andreas Kluth is a Bloomberg Opinion columnist covering European politics. A former editor in chief of Handelsblatt Global and a writer for the Economist, he is author of "Hannibal and Me.”