They really can't raise interest rates much above 5%, this follows straightforwardly from observing how much of the national budget is consumed by debt service as a function of the interest rate. (Higher rate = larger fraction of budget allocated to debt service, obviously.)
If they go above five-ish percent, this implies that they'll need to either A) raise taxes to a level that would likely inspire mutiny, B) greatly reduce borderline-impossible-to-cut parts of the budget such as the military industrial complex + welfare spending broadly construed, C) increase productivity by a lot, D) monetize the debt or E) default on the debt.
Probably they will attempt to pick F) all of these, in varying degrees, though obviously some are easier to implement than others. Anyway it is very unlikely that we will see rates much above 5% in the foreseeable future.