Most everyone had an idea that pushing Russia out of Ukraine would be a long slog, but as the summer draws to a close the war’s outcome is looking so uncertain that it will call into question the American-led response to the war machine that President Putin unleashed on Ukraine nearly 18 months ago. 

The Western appetite for quick fixes, insatiable as it is, shows few signs of being met in the broad plains and tense battlegrounds of eastern Ukraine — an assessment that some in the intelligence community go so far as to describe as a failure to meet one of the counteroffensive’s chief goals. 

That, according to a classified forecast from “the U.S. intelligence community” first reported in the Washington Post, stems from the Ukrainian forces’ inability to reach the southeastern city of Melitopol, which has turned into a strategic Russian transit hub. The assessment is “based on Russia’s brutal proficiency in defending occupied territory through a phalanx of minefields and trenches, and is likely to prompt finger pointing inside Kyiv and Western capitals about why a counteroffensive that saw tens of billions of dollars of Western weapons and military equipment fell short of its goals.”

Without taking back Melitopol, according to the brief, Kyiv will be hard pressed to achieve one of its key aims: to split up Russia’s land bridge to the Russian-occupied Crimean peninsula. 

Ukrainian forces are fighting hard, but the push they are making on Melitopol — which the Russians captured early on in the invasion — is occurring from a distance of several dozen miles. Ukraine recaptured the northern city of Kharkiv and the southern city of Kherson last year, but Melitopol is just a tougher nut to crack. It is about equidistant from Kherson and Mariupol, the port city over which Russia has maintained an iron grip mainly by having reduced most of it to rubble.

Ukraine is making incremental territorial gains, such as breaking through the minefields at Tokmak in the Zaporizhzhya region, but Russia has a trio of defensive lines running from Melitopol and has fortified villages and towns around it.

The first week of counteroffensive action in June saw Ukraine incur major casualties, according to the Post’s report, “despite having a range of newly acquired Western equipment, including U.S. Bradley Fighting Vehicles, German-made Leopard 2 tanks and specialized mine-clearing vehicles.”

The attritional aspect of the conflict was likely underestimated and it casts some doubts on the utility of supplying Ukraine with an ever-growing roster of advanced Western weaponry. Germany is likely to supply Kyiv with Taurus cruise missiles, and Denmark and the Netherlands have announced they will donate up to 61 fighter jets to Ukraine by year’s end. 

President Zelensky hailed that decision, but a U.S. Air Force general, James Hecker, commander in Europe and Africa, said last week that making F-16 squadrons battle-ready could take “four or five years.”

Adding to the problem of lag time, even though some training has already begun for Ukrainian pilots, the Dutch prime minister, Mark Rutte, said Sunday that so far that training has been limited to language lessons.

As Senator Paul told the Sun, the Biden administration recently announced it will seek an additional $24 billion for Ukraine. The senator is opposed to that expenditure, considering it excessive and fraught with the peril of waste and potential fraud. He is not the only Republican lawmaker to balk at the high tab of assistance for Ukraine. 

Ultimately, though, it may be less the price tag than operational limitations that lead to a change in not just the amount of assistance that Washington provides, but the kind of support as well. Recent comments by a top NATO official to the effect that Ukraine might have to cede territory, even though subsequently dialed back, did not come out of the blue. Ukraine’s eastern Donbas and the Crimean peninsula have been lightning rods of conflict since 2014, if not before. 

Some aspects of the crisis in Ukraine are taking on shades of the Hundred Years’ War. Even if the chief belligerents have the stomach for that kind of protracted conflict, patience in some Western capitals is starting to wear thin. Unending support for Mr. Zelensky among influential political circles in France and, critically, Germany cannot be taken for granted.

Although the ceasefire that Senator Paul has called for looks unlikely for now, in the near future President Biden will likely be handing over the keys to a new president — ideally, without falling down as he does so. The urgency for finding a way to break the stalemate that does not simply focus on delivering more weapons is likely to grow as Americans decide both what is and what is not at stake.