Consider John Kenneth Galbraith or Lester Thurow, both leading economists in the view of the general public, both with all the formal qualifications,… - Paul Krugman

The best you can say about economic policy in this slump is that we have for the most part avoided a full repeat of the Great Depression. I say “for the most part” because we actually are seeing a Depression-level slump in Greece, and very bad slumps elsewhere in the European periphery. Still, the overall downturn hasn’t been a full 1930s replay. But all of that, I think, can be attributed to the financial rescue of 2008-2009 and automatic stabilizers. Deliberate policy to offset the crash in private spending has been largely absent.

I would summarize the Keynesian view in terms of four points: 1. Economies sometimes produce much less than they could, and employ many fewer workers than they should, because there just isn’t enough spending. Such episodes can happen for a variety of reasons; the question is how to respond.
2. There are normally forces that tend to push the economy back toward full employment. But they work slowly; a hands-off policy toward depressed economies means accepting a long, unnecessary period of pain.
3. It is often possible to drastically shorten this period of pain and greatly reduce the human and financial losses by “printing money”, using the central bank’s power of currency creation to push interest rates down.
4. Sometimes, however, monetary policy loses its effectiveness, especially when rates are close to zero. In that case temporary deficit spending can provide a useful boost. And conversely, fiscal austerity in a depressed economy imposes large economic losses.

The appeal to the intellectually insecure is also more important than it might seem. Because economics touches so much of life, everyone wants to have an opinion. Yet the kind of economics covered in the textbooks is a technical subject that many people find hard to follow. How reassuring, then, to be told that it is all irrelevant -- that all you really need to know are a few simple ideas! Quite a few supply-siders have created for themselves a wonderful alternative intellectual history in which John Maynard Keynes was a fraud, Paul Samuelson and even Milton Friedman are fools, and the true line of deep economic thought runs from Adam Smith through obscure turn-of-the-century Austrians straight to them.