This month marks the 50th anniversary of a key expansion of U.S. voting rights. In March 1971, Congress passed the 26th Amendment to the Constitution, which lowered the voting age nationwide from 21 to 18. The amendment was quickly ratified by the states. Suddenly, 10 million more Americans had the right to vote.

The amendment came about thanks to years of pressure from young people. Calls to lower the voting age grew loudest at the height of the Vietnam War (1954-1975). Millions of young men—many under age 21—were being drafted to fight. The slogan “Old enough to fight, old enough to vote” became a common rallying cry. 

But since getting the vote, young Americans have consistently cast ballots at much lower rates than older people. The 2020 election saw a big surge in young voters, however. Experts think that’s because civic engagement is on the rise among kids and teens. In recent years, young people nationwide have been at the forefront of climate marches, racial justice protests, and other demonstrations.