John Ellis. Calling MMT bunk is just a measure of your being either clueless of politically motivated.

Opposition to MMT is almost entirely politically motivated, just as is the mainstream academic designed economic policies followed by neo-liberal governments

MMT does not promote a spendathon attitude to economics. There is a limit always to spending, but it is not denied by MMT, only by ignorance of it, like you demonstrate.

The spending gap is called the Output Gap. It is the difference between the current state of the economy and the best state of the economy with full employment and full usage of available resources. The difference is Trillions of dollars.

By spending into the economy the government creates wealth and raises GDP etc. It follows that deficit spending is how currency enters the economy and a budget surplus drains resources and impoverishes the economy. As to seigniorage, any profits a government makes are swallowed up by Treasury. Taxes are never used to fund federal spending, Etc.

To lose fiscal credibility is a deliberate choice made by a government, never accidental. Also one should avoid borrowing in a foreign currency. A MS government can always fund its needs from within. It has no need to go to the banks and it's a lot cheaper if they don't.