With all due respect: we heard all that before, except it was from the left, and aimed at the republican excesses of the 1980's. Regan was mortgaging our (I was the teenager then) future and We Were Not Going To Have It.
You know what happend? All those 30 year bonds came to term and we paid the mortgage without breaking a sweat. Hell, we threw in a $2T war on top. Yawn.
US federal debt is almost literally free money. Obsession about spending (oddly always spending, no one obsesses about tax cuts that affect revenue in the same way, though I do note you threw in "pensions" that AFAIK haven't been "jacked up" in Washington in literally decades) hurts, and doesn't help.
Maybe a day will come when US bond rates rise and debt stops becoming free. That's when we need to stop borrowing. Until then this kind of argument is just a political thing that people (mostly republicans these days) trot out to blandly oppose the spending priorities of the other side.