When nations and peoples allow themselves to be defined by their differences, the gulf between them widens. When we fail to pursue peace, then it stays forever beyond our grasp. To denounce or shrug off a call for cooperation is an easy and cowardly thing. That is how wars begin. That is where human progress ends.

Barack Obama (b. 1961) American politician, US President (2009-2017)

Speech, Hradčany Square, Prague (5 Apr 2009)

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