The Ozone layer, which mostly lies on the lower portion of the stratosphere.
How Long Did The Vietnam War Last. The Vietnam War is the longest war ever to have taken place in the American history. It lasted for 16 years and it was terrible for the Americans at that time as the Civil Rights campaign was at its peak and so also the Vietnam War and anti war protests.
More than 3 million people (including 58,000 Americans) were killed in the Vietnam War; more than half were Vietnamese civilians. By 1969, at the peak of U.S. involvement in the war, more than 500,000 U.S. military personnel were involved in the Vietnam conflict. Growing opposition to the war in the United States led to bitter divisions among Americans, both before and after President Richard Nixon ordered the withdrawal of U.S. forces in 1973.