It certainly looks like another example of crying wolf. Three weeks ago the World Health Organization declared a health emergency, warning countries to "prepare for a pandemic," and said the only question was the extent of worldwide damage. Senior officials prophesied that millions could be infected by the disease. But as of last week, the WHO had confirmed only 4,800 cases of swine flu, with 61 fatalities. Obviously, these low numbers are a pleasant surprise, yet one has to wonder: What did we get wrong?

Why did the predictions of a pandemic turn out to be so exaggerated? Some people blame an overheated media, but it would have been difficult to ignore major international health organizations and governments when they warned of catastrophe. I think there is a broader mistake in the way we see the world. Once we spot a problem, we can describe it in great detail, extrapolating all possible consequences. But rarely can we anticipate the human response to that crisis.

Take swine flu. The virus had crucial characteristics that led researchers to worry that it could spread far and fast. They described -- and the media reported -- what would happen if it went unchecked. But it did not go unchecked. In fact, swine flu was met by a vigorous response at its epicenter. The Mexican government reacted quickly and massively, quarantining the infected population, testing others, providing medication to those in need. The noted expert on this subject, Laurie Garrett, says, "We should all stand up and scream, 'Gracias, Mexico!' because the Mexican people and the Mexican government have sacrificed on a level that I'm not sure as Americans we would be prepared to do in the exact same circumstances. They shut down their schools. They shut down businesses, restaurants, churches, sporting events. They basically paralyzed their own economy. They've suffered billions of dollars in financial losses still being tallied up, and thereby really brought transmission to a halt.Ö "

Every time one of these viruses is detected, writers and officials bring up the Spanish influenza epidemic of 1918 in which millions of people died. Indeed, during the last pandemic scare, severe acute respiratory syndrome (SARS) in 2005, President George W. Bush claimed that he had been reading a history of the Spanish flu to help him understand how to respond. But the world today looks nothing like it did in 1918. Public health-care systems are far better and more widespread than anything that existed during World War I. Even Mexico, a developing country, has a first-rate public-health system -- far better than anything Britain or France had in the early 20th century.

One can see this same pattern of mistakes in discussions of the global economic crisis. Over the past six months, the doomsday industry has moved into high gear. Economists and business pundits are competing with each other to describe the next Great Depression. But the world we live in bears little resemblance to the 1930s era. There is much greater and more widespread wealth in Western societies, with middle classes that can withstand job losses in ways they could not in the 1930s. Bear in mind, unemployment in the non-farm sector in America rose to 37 percent in the 1930s. Unemployment in the United States today is 8.9 percentÖ . And government benefits -- nonexistent in the '30s -- play a vast role in cushioning the blow from an economic slowdown.

The biggest difference between the 1930s and today, however, lies in the human response. Governments worldwide have reacted with amazing speed and scale, lowering interest rates, recapitalizing banks and budgeting for large government expenditures. In total, all the various fiscal-stimulus packages amount to something in the range of $2 trillion. Central banks -- mainly the Federal Reserve -- have pumped much larger amounts of cash into the economy. While we debate the intricacies of every move -- is the TALF well structured? -- the basic reality is that governments have thrown everything but the kitchen sink at this problem and, taking into account the inevitable time lag, their actions are already taking effect. That does not mean a painless recovery or a return to robust growth. But it does mean that we should retire the analogies to the Depression, when policymakers -- especially central banks -- did many things wrong.

We live in a dangerous world. But it is also a world in which deep, structural forces create stability. We have learned from history and built some reasonably effective mechanisms to handle crises. Does that mean we shouldn't panic? Yes, except that it is the sense of urgency that makes people act -- even overreact -- and ensures that a crisis doesn't mutate into a disaster. Here's the paradox: If policymakers hadn't been scared of another Great Depression, there might well have been one.

The writer is editor of Newsweek International and co-host of PostGlobal, an online discussion of international issues. His e-mail address is comments@fareedzakaria.com.