http://research.stlouisfed.org/fred2/series/BASE
That shows you what actually happened to the money supply. In other words, the central factual claim made by Krugman is false:
The practical misconception here — and it’s a big one — is
the notion that we live in an era of wildly irresponsible
money printing, with runaway inflation just around the
corner. It’s true that the Federal Reserve and other
central banks have greatly expanded their balance sheets —
but they’ve done that explicitly as a temporary measure in
response to economic crisis. I know, government officials
are not to be trusted and all that, but the truth is that
Ben Bernanke’s promises that his actions wouldn’t be
inflationary have been vindicated year after year, while
goldbugs’ dire warnings of inflation keep not coming true.
As that graph shows, we are indeed in an era of out of control money printing[0]. Moreover, food[1] and energy[2] prices are through the roof, and housing is being artificially propped up by QE4 -- in which dollar holders are diluted to the tune of $85B per month[3] so that the government can take mortgage-backed securities off the hands of their favorite banks. The CPI intentionally excludes[4] the consequent energy and food price increases (ostensibly due to their "volatility") thereby systematically understating the consequences of printing 85 billion dollars per month, every month, to infinity.[0] http://research.stlouisfed.org/fred2/series/BASE
[1] http://research.stlouisfed.org/fred2/graph/?g=8l2
[3] http://www.forbes.com/sites/afontevecchia/2012/12/12/qe4-is-...