Is North Korea "stimulating" the world economy?

It seems that there is alarm over alleged counterfeiting by North Korea, which supposedly is creating a number of $100 fake bills that are hard to detect as counterfeits.

I would like to know why anyone in the USA would oppose such a thing, given that North Korea is doing what Paul Krugman in The Return of Depression Economics claimed creates a "free lunch": printing money. Why would it be OK for the Federal Reserve System to do what Krugman recommends -- directly purchasing short-term U.S. Treasury paper in order to fund U.S. Government spending -- but wrong if North Korea essentially does the same thing?

It seems to me that Krugman should be writing a blog post or column praising North Korea for its "stimulus" efforts.