We're facing the point where monetary has basically done everything it can do. Helicopter money hasn't been very effective, we can't really get beyond the zero lower bound, so the conclusion is we need fiscal policy to do something since our economy is still relatively stagnant in terms of wage increases. Sadly enough, I think it's going to be in the form of military expenditures rather than the infrastructure improvements we need.
Fiscal policy to prop up demand also includes cutting taxes.
Anyways wouldn't negative interest rates cause banks to horde money? Banks are already sitting on 1.8 million+ dollars uncommitted to loans as is so this policy sounds disastrous.