With central banks’ ability to have money created ex nihilo for the purpose of buying central governments’ debt, demand for that debt is theoretically infinite. We have attained the MMT scenario in which central governments create debt that is funded by money created for that purpose. That money flows into the economy from the central government’s purchases of goods and services and its direct payments to individuals (people employed in the central government and people receiving monetary benefits from it), with taxation as a means of tamping demand in order to curb inflation. Meanwhile, the ‘investor class’ gets to go along for the ride, with guaranteed ever-higher prices for those bonds.

So far, so good.

Eventually, though, the other class, the non-investor class, will collapse from a combination of stagnant wages, low-grade but persistent inflation, taxation, and debt accumulated in a forlorn effort to sustain a ‘middle class’ lifestyle. An external shock, such as a serious war (especially with cyber warfare becoming daily more feasible), would precipitate immediate collapse.

A better way of supplying the economy with money is possible. It is summarized in a “5 min read” here in Medium.