Laird served as defence secretary for four years starting in 1969 under president Richard Nixon.
The policies Laird developed eventually led to the gradual draw down of US troops at a time when public support for the war was declining drastically.
The goal was to convert South Vietnam's military into a force that could support itself, but the strategy ultimately failed in 1975 when Saigon fell to communist North Vietnamese forces.
Laird died of complications from congestive heart failure, David Laird said, according to the Washington Post.