Most of the money we use to pay each other for stuff and to satisfy our greed is created by banks, not by government. (It's econ 101... Google it up.) Money multiplies in banks via fractional reserve lending to 8 or 9 times its original value. When banks get constipated, money slows in circulation, and that means people get fired and stuff stops getting made and bought. We can't be healthy as an economy if our banks are afraid to bet money on loans and investments. (We can't be healthy if they make crazy bets,either, but that's the story of 2006.)
Looking at your 5 points:
(1) "QE" is the central bank putting more money in circulation, and buying up long-term debt (30-year mortgage bonds) so that the extra money will find a purpose. The goal is that the housing market will be encouraged to build more houses and issue more mortgages. Every recovery is led by an expansion is home building, but the recent economic disaster left a legacy of unpayable home mortgage debt on everybody's hands, both consumers and banks. If people can't sell their existing homes because of underwater loans, and banks fear to loan out new money, the most dynamic and job-creating part of the economy will stay in hibernation.
(2) The country as a whole has not been financially irresponsible; it's been paying down debt. Government debt is only part of the national picture, and people and businesses have spent the last five years paying down one obligation after another. In part, this is a good thing, but at the same time it means that instead of buying new stuff (and creating jobs) we are putting all our spare cash into fixing balance sheets.
(3) I guess that what you mean by this is that stimulus measures to get people spending become part of public expectations of government. For example, the Social Security withholding reduction of 2% has been a boon to me. It's an extra $3000 a year, and I've gotten accustomed to it in my monthly bill paying. I've used it to pay down old credit cards and to make advance payments on my mortgage. I've been federalizing my personal debt, you could say. I'm Trump!
(4) Sure, there are better, more direct ways than QE to stimulate housing. The problem is, the better way is through government expenditures. The Congress at this time can't agree on spending programs. In fact, a lot of them want to see any new spending offset by double reductions in existing spending.
(5) I can see no evidence of any country being injured by our central bank's QE program. Maybe your objection is a theoretical possibility, but I there's no case I'm aware of where it has become an actuality.
