One important and great speech not mentioned yet is Dwight Eisenhower's farewell address. It certainly one of the great speeches of the 20th Century. To my knowledge, this is the first speech with the phrase "military industrial complex."
Part 1
http://www.youtube.com/watch?v=5pWAGgLSCSQPart 2
http://www.youtube.com/watch?v=oACur8v1188"In the counsels of government, we must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military industrial complex. The potential for the disastrous rise of misplaced power exists, and will persist."
Another speech is John F. Kennedy's secrecy speech.
http://www.youtube.com/watch?v=xhZk8ronces"There is little value in ensuring the survival of our nation, if our traditions do not survive with it."
