I think the idea is the interest on the debt will approach our ability to pay soon. That would be like your mortgage payment being toward interest only, and you were barely able to make it.
Mostly to ourselves: https://en.wikipedia.org/wiki/National_debt_of_the_United_St...
... and we're paying less in interest on a percentage-of-revenue standpoint (blue line) than almost any other point in history: https://en.wikipedia.org/wiki/National_debt_of_the_United_St...
... and if it's truly a concern, picking the guy who ran the worst deficits in history is a... choice. https://en.wikipedia.org/wiki/National_debt_of_the_United_St...
We'll see about "projected".