<Li> February 1962--Attempted assassination of Diệm by two air force officers who bombed his palace, fails . </Li> <Li> July 23, 1962--International Agreement on the Neutrality of Laos is signed at Geneva, promising Laotian neutrality . </Li> <Li> August 1, 1962--Kennedy signs the Foreign Assistance Act of 1962, which provides "...military assistance to countries which are on the rim of the Communist world and under direct attack". </Li> <Li> October 1962--Operation Ranch Hand begins . U.S. planes spray herbicides and defoliants over South Vietnam until 1971 . </Li>

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