In 1986 Congress passed a law forcing states to raise their drinking age to 21 in order to get Federal funds for their Interstates. By 1996 everystate did. Puerto Rico has a drinking age of 18 yet they still get funds for their 3 Interstates. Why? And unlike with the states Congress could just change their law for them so why are they exempt but not say Hawaii or Vermont?
Puerto Rico is not a state.
Neither is Washington, DC but their drinking age went up (Congress may have done that itself). So Conress forced the places where it didn’t have the power to raise the drinking age to raise it for them or lose funds but let the one place where Congress does have the power to raise it keep it the same but keep their funding?