I am from Maine but have been working abroad in Ukraine and Russia since 2009. I have closely followed the growing crisis in Ukraine, daily reading newspapers from both countries and taking in the opinions of acquaintances on both sides of the conflict.

The war in Ukraine’s eastern Donbas region has reaped a terrible human cost, with around 5,000 dead and a million refugees. After seven months of brutal fighting, motivated by exhaustion and by the havoc the war is playing on their economies, Kiev, the separatists and their Moscow patrons began edging toward negotiations to end the war in November. While Moscow still refuses to acknowledge its active role in the conflict, it has publicly supported the idea of the Donbas within a united, federal Ukraine. It seems to be pressuring its separatist clients to accept such a scenario.

Unfortunately, after several meetings failed to produce an agreement, the separatists went back on the offensive, beginning with a drive on the coastal city of Mariupol. January saw hundreds of civilians dead as the two sides pounded each other’s positions in Donbas towns and cities with artillery. The separatists are calling for new negotiations that consider their recent territorial gains.

Although it is tempting to call for defiant resistance, now more than ever, the U.S. should encourage Ukraine to facilitate a negotiated settlement before the human and economic costs become untenable. Our Congress is instead reconsidering the possibility of sending Ukraine deadly arms, which it first authorized President Barack Obama to do when it passed the Ukraine Freedom Support Act in December.

In doing so, Congress risks escalating the war to a new level. Because this is in no one’s interests — least of all Ukraine’s — Obama should exercise the discretion provided for in the act and not send arms to Ukraine. Germany’s chancellor Angela Merkel set such a precedent, announcing this week that her country would not send weapons and that only negotiations can end the war.

Arming Ukraine will not lead to the desired result — military defeat of the rebels. In fact, the U.S. could never send Ukraine enough arms to counter the potent ideological weapon this action would provide the separatists and their Russian sponsors.

Civilian deaths from artillery attacks on rebel-held towns have proven the most important factor for propping up support for the separatists; if those mortars were to be supplied by the U.S. it would radically reinforce the ideological basis for “resistance to the hostile West.” We may find their perception of the conflict misguided, but its emotional power has convinced thousands to take up arms against their government or cross the border to participate in a neighbor’s war.

I don’t at all condone or romanticize the actions of the separatists. By taking up arms against the Ukrainian state, they inevitably brought violence down on their region. Moscow’s hidden sponsorship of the separatists is reckless and cynical. But at the heart of this conflict are genuine political grievances and a real ideological rift within Ukraine that will only grow wider and wider as the casualties grow on each side.

U.S. officials and media were right to perceive that the pro-western Euromaidan movement that took down President Yanukovich in March had huge popular support. Most of my Ukrainian friends are young Kiev professionals who participated in the movement, which they call their “Revolution of Dignity.” They sincerely desire Ukraine to overcome two decades of debilitating corruption and cronyism and become a state worthy of its citizens. Their aspirations deserved our support during the protests and deserve them still.

But we poorly understand the profound sense of disenfranchisement experienced by many pro-Russian Ukrainians in the country’s east after the president they voted into power was toppled by a street revolution. I have heard their perspective from a Russian coworker who was born in the Donbas and who corresponds daily with friends and family there. They perceive the revolution as a coup and the new government as a junta. Most of them voted for independence in an unofficial referendum in May. They have supported the armed separatists during Ukraine’s military offensive, in which their towns have come under sustained mortar fire.

There should be little doubt that a new offensive to vanquish the separatists with American arms will come at a horrible cost not only in lost lives, but in lost hearts and minds of these eastern Ukrainians whom Kiev must strive to bring back into the fold.

Furthermore, I fear that the ideological stakes are too high for Russia to see its clients defeated with American firepower. There is great risk that Moscow will not leave such a symbolic challenge unanswered, considering the levels of anti-western feeling in the country and the supreme strategic importance for Russia in maintaining some influence over Ukraine. We would see our move answered by a symmetrical increase in the flow of weapons and fighters into the Donbas from Russia.

A cold assessment of the risks shows how incredibly expensive total victory over the separatists would be, the cost of which would mostly be in Ukrainian lives.

With a negotiated settlement horizon at least still possible, Obama should not adopt the policy most likely to radicalize the conflict. He should not be sending arms to Ukraine.

Brian Milakovsky is from Somerville, Maine, and has worked as a forest ecologist in Russia since 2010. In 2009 he worked at the Ukrainian State Agricultural University on a Fulbright scholarship.