No-fly zone in Ukraine?

Mark P. Nevitt, The Operational and Legal Risks of a No-Fly Zone Over Ukrainian Skies. Just Security, March 10, 2022.

The United States and its NATO allies are facing forceful calls to impose a “no-fly zone” over Ukrainian skies, with the idea of countering Russian aggression in the region, easing humanitarian suffering, and protecting Ukrainian civilians trying to flee the fighting. Ukraine has requested a no-fly zone repeatedly. In the United States, polling shows this is a popular idea: three-quarters of Americans support a NATO-imposed no-fly zone. But a no-fly zone does not equate to a no-combat zone. Quite the opposite. Enforcing a no-fly zone requires the use of military force, and in Ukraine, that would likely mean confronting the Russian military head-on.