Read the excerpt from Ronald Reagan's "Tear Down This Wall" speech.Today the city thrives in spite of the challenges implicit in the very presence of this wall. What keeps you here? Certainly there's a great deal to be said for your fortitude, for your defiant courage. But I believe there's something deeper, something that involves Berlin's whole look and feel and way of life—not mere sentiment. . . . In a word, I would submit that what keeps you in Berlin is love—love both profound and abiding.