An Armoured Presonnel Carrier of the Ukrainian forces rolls in the village of Pisky, close to the airport of eastern Ukrainian city of Donetsk on December 3, 2014. (Anatolii Stepanov/AFP/Getty Images)

The writers are fellows in the foreign policy program of the Brookings Institution.

Recent reports of more troop and equipment movements into the separatist-held regions of Ukraine suggest that Russia is once again seeking to stir up trouble. The natural Western reaction has been to respond with firmness. Sanctions may be tightened; defensive weaponry may be provided to Ukraine’s underequipped and overmatched military. Given such bullying Russian tactics, this reaction is not only natural but perhaps inevitable.

Yet the Western policy response is half-wrong, and the incorrect part of it risks making 2015 just as bad a year for Ukrainian security and East-West relations as was 2014. Western policymakers do not deserve blame for the unconscionable tactics that Russian President Vladi­mir Putin has employed in Crimea and eastern Ukraine. But their actions risk reinforcing an action-reaction dynamic that will quite probably make the No. 1 victim of this crisis to date — the people of Ukraine — worse off than before.

This is not a moral question. It is entirely justifiable to provide weapons to a sovereign nation seeing its territory assaulted by a much more powerful neighbor. But regardless of right and wrong, the result of providing weapons will not be a robust self-defense capability for Ukraine. The Ukrainian military faces Russian armed forces more than five times as large and perhaps 10 to 20 times as powerful. Indeed, should such arms encourage Ukrainian President Petro Poroshenko to directly challenge Russian forces on his territory, the most likely outcome is escalation of the military crisis and a dramatic increase in death and destruction in Ukraine. Meanwhile, Russian propaganda would continue to vilify the West and sow the seeds of future crises elsewhere in Russia’s neighborhood.

Before taking such actions, and before adding permanent NATO deployments to the Baltic states — another understandable, but potentially counterproductive, reaction to the crisis — NATO leaders should attempt to work with Moscow to create a new European security order acceptable to both sides. Many Western voices will view any such effort as rewarding Russia and Putin for their miserable behavior of the past year. However, this approach would be designed not as a reward but to protect Ukraine’s security — and our own.

If the Russian people were souring on Putin, there would be an argument for simply keeping the pressure on through sanctions while threatening more to come, should he escalate. But the Russian leader enjoys 85 percent popularity at home, where many see his actions as reasonable retribution against a supposedly triumphalist NATO that has expanded right up to Russia’s borders since the Cold War, a narrative reinforced by a tightly controlled Russian media. At this point, Putin is a moderate on the Russian political spectrum.

In keeping with some of the ideas put forth by former secretary of state Henry Kissinger, and building as well on suggestions from former national security adviser Zbigniew Brzezinski — two great U.S. strategists not thought of as appeasers or wishful thinkers — the deal that we should propose to Russia would include elements like these:

●Russia can make its historically based claim on Crimea but would have to accept a binding referendum under outside monitoring that would determine the region’s future, with independence as one option.

●Russia would agree to verifiably remove its military “volunteers” from eastern Ukraine.

●Russia would permanently commit, once the Crimea matter was settled, to uphold Ukraine’s territorial security, as promised under the 1994 Budapest Memorandum covering the denuclearization of Ukraine and other former Soviet republics.

●Ukraine and the United States would agree that Ukraine would not be a candidate for NATO membership, now or in the future.

●A new pan-European security structure, building perhaps on the Organisation for Security and Cooperation in Europe , would be established with an eye toward upholding the territorial integrity of European states writ large. This association should give Moscow some sense of equal partnership and could include NATO members and former Soviet states.

●NATO would be unapologetically retained with its current membership. But because of the new security arrangement, it could eschew further enlargement and increasingly play only a supporting role in European security, refocusing on missions outside of Europe.

●The European Union would agree to work with Russia to make any possible future Ukrainian relationship with the union, including membership, compatible with Ukraine’s participation in Russia’s Eurasian Economic Union project.

●Sanctions on Russia would be gradually — and, in the end, completely — lifted as the elements of this agenda came into effect.

To be sure, Putin could claim that this agreement accomplished his core goals and portray it as a great victory. Perhaps his popularity would then rise to 88 percent or 90 percent — for a while. Then, as time went on, this accomplishment would be internalized, and Russian voters would likely hold Putin accountable for what he should have been doing all along: improving their way of life through good economic and political leadership.

Long-term Russian weakness means that the West can afford to compromise now. Russia will not have the power to dominate its neighbors for very long, no matter what the West does. Yet it could have the power and the will to foment trouble for many years absent a durable deal of the type proposed above.

Moreover, as much as it may grate now, pursuing a win-win-win outcome for Russia, Ukraine and the West is far smarter than zero-sum thinking. There is too much threat to Central Europe, and too large an agenda crying out for Russian-Western cooperation — from Iran to the broader Middle East to Afghanistan to North Korea — for U.S. security to benefit from any intensification or prolongation of the crisis of 2014. We did not start this conflict, but we can take steps that dramatically improve the chances of ending it.