The 'federal' government already has a blank check. It's called the Federal Reserve.
They can also borrow as much as they want anytime they want. There is no 'debt ceiling'.
Of course, there is practical limit on all of it. Already, the 'federal' government cannot pay it's debt, now approaching $32 trillion. It won't be long before the budget allocated to just paying the interest on the debt (not the principle!) will be larger than the budget for the entire military. Currently the Debt to GDP ratio is about 120.86% (debt divided by GDP), a horrible number. At this rate of borrowing and inflation, the budget for just serving the
interest payments on the debt will become the largest budget item in the 'federal' government by about 2027.
Fiat currency is taking a similar hit. Today's dollar is worth only $0.25 in year 2000 dollars, and only 10 mils in 1920 dollars.
Sources: Treasury Dept, Internal Revenue Service, Federal Reserve.
The 'federal' government is broke.
It can raise money in one of three ways: tax it, borrow it, or print it.
The tax base simply isn't enough. There aren't enough people to tax. High taxes cause a shutdown in the economy and quite possibly a revolt, possibly violent. A tax crash. Fortunately, not likely.
Well...it is easily seen what happens when you borrow too much. Running on tick like this is disastrous. A debt crash. Fairly likely.
Printing it is no better. That just causes more inflation. At the rate necessary to keep all of this running, printing at those levels will result in hyperinflation. The dollar will be abandoned by the people. Many are already looking around for another currency. A cash crash (most likely). In this scenario, the government will still use the dollar, but no one else will. They will convert only when necessary to deal with government crap, and by then it will be almost worthless dollars.
In any scenario, the government simply runs out of the ability to pay for itself. Already options are extremely limited. The Fed is losing control and they won't be able to get it back. The result is uncontrolled shutdown of government programs to shed costs. This of course will result in revolt, quite possibly violent. The military won't be there to protect them. They must be paid, and the funny money they are being paid with is next to worthless.