As the socialist German chancellor in the 1970s, Brandt presided over “change through closeness.” A web of economic and other ties were established between East and West Germany. Relatives from East and West were allowed to contact one another. Brandt also reached out to the Eastern bloc and the Soviet Union to show genuine repentance for Nazi war crimes. Every subsequent German leader followed Brandt’s path.

The wall forced West Germans to face reality: The U.S. wasn’t going to war over the Berlin Wall; East Germany wasn’t going away; and trying to isolate it would only strengthen the hand of communist hard-liners. The shrewder policy was to encourage as much contact as possible with the West. The more East Germany was exposed to the West, the more it was coaxed out of its communist shell. The idea promulgated by the Eastern hard-liners, that West Germany was a military threat on the order of Nazi Germany, became increasingly implausible. Ultimately, detente amounted to a liberation policy.

Absent Brandt’s insistence on detente, a new generation in the Kremlin, led by Mikhail Gorbachev, would never have had the confidence to allow East Germany to reunite with the West. Instead, they might well have clung to the vision of West Germany as a hotbed of revanchist Nazis that Stalin’s and Khrushchev’s generation saw.