A main goal of President Richard Nixon's policy of detente was to 2. reduce tensions between the United States and the Soviet Union. Keep in mind that Nixon led the US around some heated moments in the Vietnam War. As such, he sought to ease tensions elsewhere. In French, the word actually means "relaxation."
"IT IS BETTER THAT A FEW SHOULD PERISH THAN THAT OF THE WHOLE CITY" I hope i helped :-)