It is possible. It happened after the Great Depression. But I doubt that this crisis will change the world anything like as profoundly. In the end, I doubt it will even overthrow much of the conventional wisdom about states and markets.

In thinking through the parallel with the 1930s, the important question is how far the financial emergency will infect the rest of the economy. The Depression changed the US and the world because it wrecked the lives of countless millions of people.

The US and many other countries face a bad recession - but surely nothing to compare with that sustained catastrophe. Ragged as the response to this emergency seems, we will look back and say that, compared with previous crises, the remedies were both prompt and massive. Notwithstanding the past few weeks' arguments about how to stabilise the situation, we will also say that consensus was achieved with surprising speed - and that the willingness to support it with sufficient resources (meaning without limit) was never really in question. In short, the mistakes of the 1930s are not being repeated.