Modern Monetary Theory
This is the economic theory that A-OC and others use to justify debt spending. The article does a good job at debunking the theory. Essentially it advocates that money has no intrinsic value therefore debt has little meaning. Read why at the link.
You may not have heard about the fringe concept of Modern Monetary Theory (MMT), but you can expect that you'll hear a lot more about it in the future as Democrats pretend the theory supports the plausibility of fiscally outrageous policy proposals like the Green New Deal.
The greatest public strength of the theory is that you don't have to understand much about economics to embrace it. Like socialism, it's anything but a new idea, but it's somehow hip for our growing number of underemployed liberal arts majors to subscribe to it and feel intellectually superior for doing so.
MMT, you see, requires that you eschew any realistic understanding of money, which is easiest to do for those who've yet to, or have failed to, earn substantial amounts of it in a free market.
Most everyday people can simply accept that money, or currency, has a specific value tied to it. If it did not, you wouldn't go to work every day in order to exchange your labor for an agreed upon sum of money. The restaurateur down the street would not feed you in exchange for money at an agreed upon price if money didn't have a specific value. Neither of you feels that your efforts are simply charity meant to feed the government leviathan, which determines what your money is worth, do you?
It's really that simple, and this is where MMT fails on its most fundamental proposition. Money has a going market value that we recognize every single day, and it is tied to a marketplace.