Why did the voting age change?

The voting age was lowered from 21 to 18 primarily due to the argument that if individuals were old enough to be drafted for military service during the Vietnam War, they should also have the right to vote. This movement gained momentum in the 1960s and culminated in the passage of the 26th Amendment to the U.S. Constitution in 1971. The change aimed to ensure that young adults had a voice in decisions that directly affected their lives, particularly in matters of war and peace.