After a lengthy policy review and a considerable amount of discussion, the White House decided in December to overturn the previous administration’s position on U.S. weapons sales to Ukraine, an arms exporter. Washington would now approve lethal defensive weapons systems to Kiev ostensibly in order to improve Ukraine’s ability to defend itself against Russian-backed separatists operating in the east of the country. The State Department announced the first significant sale March 1 of 210 Javelin anti-tank missiles and 37 launchers with an estimated value of $47 million.

Some leaders in Washington have advocated for the sale of missiles to damage or destroy Russian tanks in eastern Ukraine ever since Moscow intervened in its neighbor’s affairs. These weapons, however, will have no impact on the fighting beyond a front line that has been mostly static for years.

Beyond the battlefield, however, this will further poison whatever bilateral relationship the U.S. has left with Russia — and that is bad for America.

Sending arms to Ukraine is far more likely to escalate a conflict whose outcome is vital to Russia’s national security interest and, at best, peripheral to America’s. While deterring more violence in eastern Ukraine may be the stated objective, shipping advanced weapons into a conflict zone is bound to end up badly for Ukrainians — who simply want the violence to end — and for the United States, a country that should not be plunging into another tangential foreign policy commitment.

At every point in the conflict when Kiev’s army was advancing on the ground, Russian President Vladimir Putin responded by pouring more military equipment, money and Russian military personnel into the Donbass on behalf of the separatists. The reason Moscow has responded in such a way to prevent a complete separatist collapse is realpolitik, plain and simple: Ukraine’s political loyalties are immensely important to Russia.

It is simply inconceivable for Putin to allow a large neighboring state — that has historically been a connective tissue to the old Russian empire and the Soviet Union — to drift closer to Europe and act antagonistic toward Moscow. This is a strategic vulnerability for Russia, and one that he relies on as a buffer from perceived encroachment by liberal internationalists.

Many in the West scoff at the idea that Russia’s desire for pliant neighbors or a strategic sphere of influence justifies its violation of Ukraine’s territorial integrity. And indeed, these voices certainly have a point; was it not for Moscow’s military support in the form of hundreds of tanks, armor, air defense systems and intelligence assets, Ukraine’s war would likely be over and the Ukrainian military would be combing the Donbass today and reasserting Kiev’s control.

Policymakers in the West rightly disapprove of Russia’s actions, and we should not excuse Moscow’s policy. But our responsibility is to understand why the Russians are doing what they are doing so we can make informed, strategic decisions about how and where we must push back against them — the answer is not everywhere and always.

Moscow, like Washington, wants to be the dominant power in the region. Weapons shipments to Kiev, in the view of the Kremlin, are a hostile act designed to jeopardize Moscow’s national security and pressure Russia. To the extent that this view continues to prevail, the Kremlin will react forcefully and retaliate. This fundamental truth must factor into Washington’s decision-making.

At its heart, international politics is about strategic competition between states. It is a cutthroat game that forces all countries, including the United States, to make wise, informed decisions about which battles are in the national interest to fight and which are left for the region itself to manage.

Picking a fight with a declining, nuclear power over Ukraine is the exact opposite of wise; remember, Ukraine is not an ally. Russia has so much more at stake in the outcome than the U.S., so the former will always be more willing to make the necessary sacrifices to achieve its desired political end state.

In many respects, the Trump administration’s decision to send anti-tank missiles to Kiev is a perfect example of Washington’s reactionary, rather than strategic, foreign policy. Sometimes it is appropriate for the United States to respond harshly to Russian behavior, notably when the malignant behavior conflicts with our vital interests — our security, prosperity and our republic. When no vital interests are at stake, however, it is more appropriate to collaborate with Moscow in an attempt to resolve a dispute diplomatically. And in still other areas — strategic arms control, for instance — the U.S. and Russia have a responsibility to work together in order to promote mutual understanding between the two nations.

The bipartisan foreign policy establishment in Washington ought to adopt a page out of the realist textbook: Intervening in peripheral conflicts that are separate from America’s core national security interests is a drain on America’s limited resources and a dangerous step toward unnecessary confrontation. It’s past time to start taking advice from those who counsel more restraint in national security decision-making.

Daniel DePetris is a fellow at Defense Priorities.