Why is age 18 considered adult?

According to Slate, there is no official reason why age 18 is considered adulthood, but it is believed to be tied to voting rights. Before the 26th Amendment in 1971, people had to be 21 to vote. As a result, most states considered age 21 adulthood.

Slate says that the age to vote was lowered to 18 during the unrest of the Vietnam War. During this time, the draft saw people as young as 18 forced into war. Citizens argued that if people were old enough to be forced into war, they deserved the right to vote on the lawmakers who were sending them into battle.