On Wednesday President Biden gave a speech from the White House calling on Congress to pass aid for Ukraine. He tried every trick in the book: pointing to the domestic economic benefits of military spending, highlighting the national security implications of aid, and even accusing Republicans in Congress of giving “Putin the greatest gift he can hope for”. Hours later, every single Republican senator voted against the bill that would have given more aid to Ukraine. It’s just the latest setback for Ukraine, as something that had until only months ago been considered almost inevitable – continuing US funding for the war – has become highly uncertain. It’s a signal of the extent to which Ukraine aid has become a political football in the US, and a sign that it is likely to feature as a point of contention in next year’s presidential campaign. The controversy could not have come at a worse time for Ukraine. The country’s much anticipated 2023 counteroffensive has yielded few gains, western support is declining generally, and the winter is likely to see another extensive Russian bombing campaign. The war in Gaza is taking attention and resources away from Ukraine, and recriminations about the failed winter offensive – along with signs of discord among Ukrainian leaders – have begun to appear in strategic news leaks. At the same time, many of these problems were foreseeable, even months ago. The American public, wearied by two decades of war in Iraq and Afghanistan, was never going to support a lengthy, stalemated war in Ukraine, especially when the conflict has already cost the American taxpayer more than $75bn (£60bn). It is also hard to imagine Ukraine’s allies prioritising defence investment and meeting the embattled country’s significant ammunition and equipment needs in a time of economic slowdown. Indeed, even a successful Ukraine counteroffensive wouldn’t have solved all these problems. But as a recent Washington Post exposé highlighted, Ukrainian forces didn’t meet even the minimum bar for success in that campaign. Troops were hobbled by a mismatch between US and Ukrainian views of strategy, some poor tactical decisions on the part of the Ukrainian leadership, and Russian defensive fortifications that proved far more solid and effective than expected. In early November, Ukraine’s top general, Valerii Zaluzhnyi, admitted to an interviewer that the war was at a stalemate. After 18 months of triumphalist rhetoric, reality is beginning to set in. Now policymakers in Kyiv and their western partners must answer some challenging questions: how much territory can Ukraine realistically recover through military means? How long will western public opinion continue to support funding the war? When does failure to invest in our defence industrial base mean that our stockpiles are insufficient to resource Ukraine? Perhaps the most important question in the short term is that of US funding. The country has provided the lion’s share of military aid to Ukraine since Russia’s invasion, and though Congress may eventually approve more Ukraine spending, it’s notable that even Republican hawks such as Lindsey Graham continue to insist that any further aid be tied to immigration reform, a notoriously difficult topic under any circumstances. If Congress does not approve further spending in Ukraine, the burden will pass to European states, some of whom are also increasingly concerned about the costs of supporting Ukraine. It will place Ukraine in a difficult – though not necessarily catastrophic – position. The country was already beginning to pivot to defence, hunkering down for the winter and seeking to fortify current lines against future Russian attacks; a shortfall in aid will only make that shift more urgent. The big long-term question for the Biden administration is what US policy towards the war looks like going forward. Thus far, the administration has been curiously unwilling to consider the future course of the war and whether it is sustainable. Publicly, the president has mostly doubled down on his tough rhetoric, telling Congress that they must vote for aid or let Putin win. But given the present circumstances, the administration needs to formulate a plausible plan B for how to proceed – whether or not Congress approves additional funding. There’s relatively little point in pushing for a ceasefire: so long as Moscow perceives the potential for a Donald Trump re-election in November next year, Russian leaders are unlikely to agree to a deal. But the groundwork could be laid now by opening lines of communication with Moscow, and beginning a frank and open conversation with Kyiv and other European allies about the endgame of the war. They also need a better narrative. For much of the last year, the White House has argued that US support should be focused on helping Ukraine retake territory. But this limits US policymakers and makes the failure by Ukraine to retake territory a Russian win almost by default. Instead, the White House should seek to build a new narrative: that this is a war of defence for Ukraine, and a strategic defeat for Russia, and that the US can support Ukraine while also acknowledging that there are other national security priorities that might need to take precedence. This narrative is less aspirational, but more pragmatic. Attempting to transition the war in Ukraine to a lower-stakes defensive conflict in the next year will not necessarily be popular, either in Kyiv, or among US allies in Europe. Nor is it a plan that would win the war or offer significant territorial gains. But it is a plan that can prevent Ukrainian losses. And most importantly, if the Biden administration is re-elected in November, this approach would place them in a much stronger position to pursue armistice negotiations in late 2024. Emma Ashford is a senior fellow with the Reimagining US Grand Strategy programme at the Stimson Center, Washington DC, and the author of Oil, the State and War