The vote is the most powerful instrument ever devised by man for breaking down injustice and destroying the terrible walls which imprison men because they are different from other men.
Lyndon B. Johnson (1908-1973) American politician, educator, US President (1963-69)
Speech (1965-08-06), Signing of the Voting Rights Act, Washington, D.C.
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(Source (Video) at 15:15)