Nothing Like It in the World is Stephen Ambrose's account of the men who built the transcontinental railway -- the investors who profited mightily from their high-risk gamble; the politicians who understood the economic and social importance of a steel ribbon to tie the country together; and the engineers, surveyors and laborers who made it real -- often costing them their lives.

Today we take the railway for granted -- if we think about it all. The same goes for the interstate highway system, the electrical grid and the Internet. Each is a network in its own right, and all are aging and need new investments to meet needs and expectations of modern communities.

Massive volumes of freight traffic have shifted from the railway to the interstate, leaving both infrastructures in disrepair. Millions of miles of rail lines are abandoned -- long stretches of interstate highways just feel that way.

In August, 50 million Americans were left in the dark when the eastern electrical grid imploded through a series of cascading failures in its transmission network. And the Internet was subjected to a rapid succession of malicious code attacks that raised serious questions about its resiliency.

There is a problem when deliberately cryptic names such as Lovsan, MSBlaster, Sobig.F and Welchia become part of everyday conversations. The exceptional event causes us to question the routine reliability of critical infrastructures. There are people whose life work is to worry about such things, as it should be. When that worry spreads to the general public and is fueled by wild-eyed speculation in the media, it contributes to a crisis in confidence in things otherwise taken for granted.

Information security technologist Bruce Schneier warns against wrong-headed thinking at times like this, "[People] think, 'How do I avoid the threat?' when they should be thinking, 'How do I manage the risk?'" The mistake is seen in apparently serious suggestions that states should wean themselves from the grid, and information systems should stand alone -- as if avoiding the threat is more valuable than advantages in productivity, cost effectiveness and quality of life that come from being part of a networked world.

The primary risk at this moment is snatching defeat from the jaws of victory. Even as 72 percent of American households are connected to the Internet, including one third through broadband connections, fear of exposure and the hassle factor is dampening enthusiasm for the ribbons of silicon that tie communities together. The question for governments is whether they are playing at the Internet, or playing for keeps.

Owing to its organic architecture, the Internet is more malleable than other public infrastructures in responding to changing needs and increasing demands. But as recent events demonstrate, a "self-healing" network recovers only with the help of its connected entities, and at a considerable cost.

It is this factor the Internet shares with the electrical grid, the highway system and the railroad -- there are insufficient public funds to refurbish and enhance these public infrastructures. To those who ask for greater public investment -- whether to rebuild the electrical grid or Iraq (which apparently have about the same price tag) -- the response is perhaps best summed up by West Virginia Sen. Robert Byrd: "Congress is not an ATM machine."

With the public treasury otherwise committed, new investment will necessarily come from the private sector -- if it comes at all -- but only if companies can be handsomely rewarded for their risk. That is not a popular idea these days, coming in the wake of revelations about scandals in corporate accounting and governance. We do not like robber barons, but enriching them was the trade-off for building infrastructures that would not be built under other circumstances.

Now, of course, names of railroad barons are associated less with greed than as underwriters of hospital wings and public radio programs. As for the railroad itself -- left for dead years ago as it stumbled amid growing problems -- it has enjoyed a reversal of fortune, with freight traffic increasing by as much as 20 percent in the last year alone. It's a lesson worth paying attention to.

Public CIOs must be willing to risk their reputations on a long-term view of the Internet, even as headlines make their bosses and colleagues nervous, because there is nothing like it in the world either.