Rapprochement

The word is also used in a personal sense: when friends or family members who are in conflict or have become estranged reestablish a friendlier relationship, they achieve a rapprochement.

[4] The Entente Cordiale was a series of diplomatic agreements between the United Kingdom and France in 1904 that saw the warming of relations and simplification of overseas borders.

Rather than a formal agreement to military aid, the Entente Cordiale grew with the various diplomatic crises leading up to World War I.

[3] The mending of relations between the United States under Richard Nixon and the People's Republic of China from 1972 onward can be considered to be rapprochement.

This was partially in response to construction of missile defense systems, which would allow a nation to launch a first strike and shoot down retaliation.