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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