The low rates keep the cost of gov’t debt low. If rates go up, all budgets (such as they are) get thrown out of whack. The cost of debt service will force choices on spending and taxes that politicians don’t want to make.
Winner. Debt servicing costs will mushroom. And inflation will rise causing increased entitlement program costs. The stock market will plummet. The Fed holds 4 trillion of our 18.8 trillion national debt. The Fed is riding on the back of a tiger and has a hard time getting off.