No war is a one-sided affair. There is no sound to one hand clapping.

Russia’s assault on Ukraine is an unambiguously bad thing. But it didn’t happen in a vacuum. In order to solve the problem, we have to first understand the context in which it occurred, and the part that the U.S. played in its happening.

The Big Bang in U.S.-Russian relations was the breakup of the Soviet Union in 1991. Then-U.S. president George H.W. Bush and his Secretary of State, James Baker, promised Mikhail Gorbachev that if he agreed to the unification of Germany, NATO would not expand eastward, toward Russia, “not one inch.”

That promise was broken almost immediately when, in 1999, Bill Clinton helped usher Poland, Hungary, and the Czech Republic into NATO. Russia considered this move not just a betrayal, but an act of aggression. First, Poland is an implacable enemy of Russia, and has been for centuries. And NATO had just finished bombing Russian ally Yugoslavia out of existence. The “slav” in Yugoslavia signifies the same ethnicity as the Slavs who are the Russian people.