29 years ago tonight the Wall came down. I watched it on tv in awe, after having visited East Berlin two years earlier. The Wall has now been down a year longer than it stood. That is quite an intriguing fact. When I grew up it seemed such an immutable reality. Then the whole thing lost its power overnight. Also makes me think about which of our institutions you’d like to keep are just as brittle. Such sudden phase shifts don’t apply only to the ones you’d like to see gone.

Potsdamer Platz, an empty kill zone, as I visited in 1987

Potsdamer Platz, bustling city center, as I visited in 2014.