When I ran for Presidency of the United States, I knew that this country faced serious challenges, but I could not realize — nor could any man realize who does not bear the burdens of this office — how heavy and constant would be those burdens.

John F. Kennedy (1917-1963) American politician, author, journalist, US President (1961–63)

“Radio and TV Report to the American People on the Berlin Crisis” (25 Jul 1961)
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