Identify the Counterculture Movement Associated with 'Make Love, Not War'

During the 1960s, a significant counterculture movement emerged in the United States, challenging mainstream societal norms and advocating for various social changes, including civil rights, environmentalism, and peace. This movement comprised a diverse group of activists and individuals who often rejected traditional values, opting instead for alternative lifestyles, increasing experimentation with drugs, and an emphasis on personal freedom and self-expression. To what movement within this counterculture is the phrase “Make love, not war” most closely associated, reflecting the anti-war sentiment of the time?