Opinion | Ukraine’s offensive is coming. But keep your expectations in check.

It bears repeating, though, that most analysts expected a swift Russian victory when Vladimir Putin unleashed his ruinous invasion nearly 15 months ago. They were wrong. Ukraine’s military forces — highly motivated, ably led, technically agile and fighting, it’s worth remembering, for their homes, families and very national identity — have shocked the world with their success. Despite massive numerical inferiority, they held off a far more powerful invader intent on a land grab. And over the course of a few months last summer and fall, they pushed Moscow’s forces back from more than 10,000 square miles of territory✓ taken in the war’s initial weeks.

It’s also worth recalling that much of their success took place before the United States and its NATO allies provided much of the staggering quantities of arms and munitions as well as training that have now been rendered to Kyiv’s forces. The coming clash will be a measure not only of Ukraine’s resolve and skill, which it has already proved in spades, but the effective use to which it can continue to put some of the West’s most advanced weapons.

Unfortunately, the stress in that assessment needs to be on the word some. Because while the gusher of Western materiel to Ukraine has been impressive, it has also been too slow and barely adequate to the task at hand: forcing the retreat of one of the world’s five biggest militaries.

Ukraine’s top military commander, Gen. Valery Zaluzhny, said in December his forces needed 300 main battle tanks, an assessment some analysts regarded as conservative. His forces have received about 230. Ukrainian President Volodymyr Zelensky and his government have pleaded for long-range missiles, specifically a U.S.-made system known as ATACMS. Those have been denied by President Biden. So have F-16 fighter jets, which the Ukrainians also badly want. And the West’s ability to produce and ship artillery ammunition, which has been the Ukrainian military’s bread and butter for most of the war, has been all too finite.

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That does not mean Ukraine’s offensive is doomed. It does mean that Washington and its European allies have not quite matched their full-throated rhetorical support of Ukraine with an unbridled supply of the weapons that Kyiv, and many military experts, believe Ukraine’s soldiers need. Ukraine has been helped enormously by Western provisions. An imponderable of the future fighting will be how things might have gone differently, or better, if the West had sent more.

Despite Ukraine’s astonishing battlefield successes so far, Putin’s forces still occupy about 18 percent of Ukrainian territory, including Crimea, which Moscow seized in 2014 and then annexed, illegally. Kyiv’s coming counteroffensive is aimed at regaining as much of that territory as possible. Given Russia’s inherent advantages — especially the sheer size of its forces and an unfettered industrial mobilization in support of the war — Ukraine should get credit for recapturing any territory. Unfortunately that is not likely.

Putin has calculated, probably correctly, that time is his ally, and that the West’s commitment to Kyiv will sooner or later be subverted by “Ukraine fatigue,” exacerbated by the cost to European and American taxpayers. Ukrainian leaders agree with that assessment and therefore are fully aware that they are underdogs not just on the battlefield but in the parallel struggle over expectations management. Making major territorial gains will not only be a boost to the morale of Ukraine’s own troops and citizens, it might also be a necessary precondition of maintaining the West’s flow of arms. “I believe that the more victories we have on the battlefield, frankly, the more people will believe in us, which means we will get more help,” Mr. Zelensky told The Post in Kyiv last week.

That is a clear-eyed assessment. It is simultaneously true that whatever obstacles, setbacks, reversals and disappointments that Ukraine may suffer — and it will surely suffer some — should not lead to premature conclusions that its counteroffensive has failed. In fact, Ukraine, with the West’s help, has already won an enormous strategic victory by standing up to Mr. Putin’s unwarranted, bloody-minded aggression and exposing Russia’s military as the poorly trained, badly motivated, ill-disciplined and ineptly led force that it is.

The Kremlin has tried to dismember and erase a sovereign state from the map. It has failed. But the fight to force the further retreat of Russia’s troops continues.Ukraine’s fight is the free world’s fight — for the bedrock right of any country to choose its destiny as part of the club of democratic, pluralistic and tolerant nations. The West should not waver — before or after Ukraine’s offensive — whether it moves the front line miles or mere inches.