Opinion | A NATO No-Fly Zone Would Escalate the Russia-Ukraine War

Even the strikes that come from aircraft may come from planes far away, rather than overhead: the cruise missile barrage against the Ukrainian military base at Yavoriv was launched from aircraft that never left Russian airspace. A no-fly zone would not stop such threats. And when it becomes clear that such a zone is not enough, as happened in Bosnia in 1995, the United States may soon feel pressure to expand its military operation to strike additional targets on the ground, further drawing it into the conflict.

Indeed, past experiences reinforce the need for caution. Since the 1990s, the United States and its allies have imposed no-fly zones in northern and southern Iraq, Bosnia, and Libya. In none of those cases was the United States trying to impose a no-fly zone against a military with Russia’s capabilities, or one with the ability to retaliate with nuclear weapons. Moreover, all had mixed results when it came to protecting civilians.

In 1995, even with a NATO-imposed no-fly zone in effect, Serb forces perpetrated a genocide against Bosnian Muslims at Srebrenica and killed dozens of civilians in a mortar attack on Sarajevo’s Markale Market. After the no-fly zone’s failure to prevent such horror, NATO then expanded its intervention in Bosnia, carrying out additional strikes on ground-based threats to civilians such as Bosnian Serb artillery and arms depots. A similar situation could play out in Ukraine — only with the added risk of escalation.

This isn’t to say that the United States and its NATO allies should not be helping Ukraine to “close the sky” by other means. From the start of the war, Ukrainian air defenses have done serious damage to Russian aircraft. Although difficult to verify, according to Ukraine, its forces have destroyed 101 Russian planes and 124 helicopters as of March 23. They’re poised to get even more lethal: After Mr. Zelensky’s address to the U.S. Congress, the White House announced an additional $800 million in security assistance to Ukraine — adding to the anti-tank and antiaircraft weapons already provided — including some 800 Stinger shoulder-fired antiaircraft systems and switchblade drones, capable of both observation and attacks on targets such as Russian artillery. It is also reportedly exploring whether European allies could transfer Soviet-made S-300 long-range surface-to-air missiles to Ukraine.

It is important to recognize the significance of the measures the United States and others have taken to assist in the defense of Ukraine. The overt transfers of weapons to Ukraine — weapons intended to kill Russian forces — are themselves a remarkable and potentially escalatory step. So far, that does not appear to have crossed Moscow’s redlines for military retaliation against the United States.

Seeking to deprive Russia of airpower in the conflict would be an extraordinarily dangerous gamble with uncertain payoff. The Biden administration should remain resolute in rejecting such proposals, which, although presented as half measures to avoid direct war between the United States and Russia, are in fact tantamount to exactly that war. The United States and its NATO allies must continue to help Ukraine. But they must also do their part to avoid escalating that conflict, as the costs of doing so could well be unfathomable.