 Somewhere in my desk is a piece of concrete. It is odd-shaped, having been shipped off a wall. But not just any wall. It's a small remnant of the Berlin Wall from the trip my husband and I took to Germany in the early 1990s. I'm Johnny Erickson Tata. And remember when President Reagan stood before the Brandenburg Gate and issued that famous challenge? Mr. Gorbachev, tear down this wall. Well, two years later, it came down.