The exact "whys" don't really matter. In the end, it will be obvious if this printing press mania of Bernanke and Barry was a good thing or a bad thing. The evidence, if it goes badly, will be overwhelming. Let's wait a bit and see the results.
My guess is, the PTB are at least not 100% confident, or they would not be buying a few BILLION rounds of ammunition, and Barry would not see the need for a DOMESTIC police force as strong as our multi-TRILLION $$$ military, would you?