Commentary There are several historical referents we should keep in mind about the Ukraine war. First, no-fly zones. Lots of Westerners are calling for NATO aircraft to establish a no-fly zone above Ukraine to stop Russian bombing of Ukrainian cities. That is a terrible idea. Russian planes can still launch missiles from the nearby airspace of Russia and Belarus. No nation in history has declared a no-fly zone against an adversarial nuclear power. No-fly zones are best known from the 12-year air block over Iraq in between the two Gulf Wars. NATO also imposed a no-fly zone over Bosnia and Herzegovina in the 1990s, and again over Libya in 2011. These efforts were aimed respectively at the bloody though small-time dictators Saddam Hussein, Slobodan Milošević, and Muammar Gaddafi. None had nuclear weapons. Eventually the air patrols withered away. Often allies bickered about their relative contributions. Sometimes the zones failed to …