National debt was around 4.5 trillion. The 9/11 wars bumped us up to 9-10 trillion then Obama (millennials favorite president) saw us through to 19.5 trillion.
But I don't blame millennials for that debt. What I do blame them for is their response to it: which is "gimme socialism!" (more debt). Millennials want to act like they're this genius generation that was dealt a poor hand when it's almost the exact opposite