John Avlon on Reagan's Defiant Berlin Wall SpeechTEAR DOWN THIS WALLDaily Beast editor-in-chief John Avlon defends Ronald Reagan’s famous Berlin Wall speech as one of history's most defiant moments.The Daily Beast VideoJohn AvlonUpdated Apr. 13, 2017 3:44PM ET / Published Jun. 03, 2016 12:49PM ET Courtesy of the History Channel