A country's debt is all about it's taxes it receives as revenue and its resources available to repay it like gold reserves and oil. The country sells bonds to banks etc with a guaranteed interest rate payable over a set period of time to fund the economy but it has a ceiling, it can borrow it's way out of trouble to a certain extent but then like a pyramid scheme it will eventually all crash down. This is when they get desperate, raise interest rates to make us attractive again to investors and finally crash the economy. 1967 and Black Wednesday are examples.
This covid thing is different though as it affects the whole world so I think a lot of leeway will be allowed. When it's all over though one things for sure, tax and interest rate rises will hit us hard.
Interest rate rises will devestate a whole swathe of the population. Imagine all the people who've bought houses with hefty mortgages who can't survive much of a rate hike. Generally quite a productive part of society
But if it has to happen it has to happen.
End of the day, costs up, income down.. Can't ride that forever and its way we are heading currently.