It has been years since rescuers finished combing through the gruesome wreckage of Manhattan; years in which analysts have struggled to piece together the madness behind the attack. We can still only speculate about the motives that drove men into the air, into the buildings. We can only shudder at the long-term implications of the United States’ war on terrorism and the personal tragedies let loose in the process. We know that the death toll from Afghanistan and Iraq is in the thousands, and that the financial toll will soar to billions and billions of dollars.

There are other things, though, that are also obvious from the events of Sept. 11, things that should have been obvious even without the devastation let loose on that day.

First is that the new economy never was all that different from the old. In the ancient, heady days of the Internet boom, it became fashionable to declare that the physical bonds of commerce had been replaced by the virtual. Pundits and investors spoke giddily of the end of national borders, of markets that spanned the globe and replaced the hefty weight of machines and plants with ephemeral bits of information. This may be true. We do have global markets and firms whose value is based only on the knowledge they provide. But the advent of the virtual economy did not remove the constraints of the physical.

Planes smashed into buildings in September 2001, and information was incapable of stopping them. Firms lost physical assets – computers, files, desks and offices – that could not immediately be replaced. And they lost people, whose knowledge and expertise proved irreplaceable.

A second grim lesson is that governments do indeed matter. We have heard a lot, again, in recent years about the coming obsolescence of the nation state. We have been told that the new economy would push power away from states and towards the market, and that smart governments would be the ones that simply let commerce take its course. It’s a logical argument, but it’s wrong. For look what happened in the immediate wake of 9-11. People didn’t want representatives of Morgan Stanley to deal alone with what had befallen them. They didn’t turn to American Airlines. Instead they wanted firefighters and police officers and armies. They wanted Rudy Giuliani to take care of things while the folks in the Pentagon figured out what to do next.

In the days and weeks that followed, Americans quietly welcomed government back into many aspects of market life: into airports and buildings, rental cars and flying schools. We also began to reconsider Clinton-era policies that reversed the government’s historical control over encryption technologies, the complex formulas that allow Internet or cell phone users to scramble, or disguise, their communications.

In the late 1990s, the Clinton administration gingerly stepped away from these controls, ignoring the pleas of the FBI in favor of arguments that controls were bad for commerce. Tragically, it appears that the FBI was right, and that Americans may want to allow the government considerably more leeway for listening in.

Finally, the scariest and most obvious lesson of our newfound insecurity is that U.S.-style capitalism is not necessarily a panacea for the world’s ills. In the new economy, all of the world was supposed to follow the trail laid down by the United States. It was a trail dominated by high-tech firms, by financial firms, by the information-based giants that drove U.S. prosperity to unprecedented levels in the 1990s. In many parts of the world, however, this trail has long been seen as the wrong road.

People resent the United States for its prosperity, for its power, and for the presumption that prosperity and power give it the right to judge and advise others. Thankfully, most of the world’s people do not act upon this resentment. But it is there and it is simmering.

We saw the tragic explosion of this backlash on Sept. 11. And, terrifyingly, we are likely to see it again.

Debora L. Spar, a featured speaker at the Camden Conference (to be held Feb. 27-29 at the Camden Opera House), is the Spangler Family Professor at Harvard Business School and author of the recently published “Ruling the Waves: Cycles of Discovery, Chaos and Wealth from the Compass to the Internet.”