1969 U.S. troop deployment reaches highest point of the war in April: 543,000. President Nixon begins U.S. troop withdrawal on May 14.
1970 U.S. and South Vietnamese forces cross Cambodian border to get at enemy bases (April 30).
1971 U.S. bombers strike massively in North Vietnam for alleged violations of 1968 bombing halt agreement (Dec. 26 to 30). U.S. troops number 140,000 at year's end.
1972 North Vietnamese launch bombing offensive across demilitarized zone (March 30). U.S. resumes bombing of Hanoi (April 15); U.S. announces mining of North Vietnam ports. Last U.S. combat troops leave (Aug. 11).
1973 Cease-fire accord signed (Jan. 27); last non-combat U.S. troops withdraw from Vietnam (March 29); last U.S. prisoners of war released (April 1). Some U.S. civilians remain.
Read more: Vietnam War - The War In Vietnam - Vietnamese, South, North, Military, Troops, and Bombing
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