Whether Onel de Guzman’s Love Letter computer virus and worm is a source of national pride, as his local paper is reported to have proclaimed (“The country’s first world-class hacker,” read one headline) it was instantly ruinous and certainly costly to computer users worldwide. Though the college student seems as chagrined by the virus as anyone, he alleged misdeed suggests that the next great computer advance will have less to do with speed or miniaturization and a lot to do with security.

The bug targeted a narrow segment of the Internet world: A specific e-mail program running on a specific computer operating system. If a computer missed just one of the three requirements — an Internet connection, the Outlook e-mail program or the Windows 95/98/NT/2000 operating system — it was unaffected.

Perhaps it was happenstance, or the journalist’s creed of objectivity, that led Time magazine to place Bill Gates’ defense of keeping Microsoft intact on a facing page with a short article that blames the close ties between Windows and the Microsoft Office software package for the virulence of the Love Letter virus/worm. (A virus infects files on a computer; a worm replicates itself across networks or via disk swapping.)

There is little doubt that the “Love Bug” was able to stomp on so many computers because of the popularity of Windows and Office. Microsoft has intentionally designed its Office programs to take full command over the Windows operating system in a way that other programs cannot; Mr. Gates admits as much in his Time article. He also notes the productivity and ease of use generated by the Office suite as proof of the benefits of that interactivity; millions of computer owners worldwide have discovered the downside to such interdependence.

Interoperability is the central concept behind the Internet. The ability of one computer — regardless of its operating systems, file structures, place on the globe or the programs it runs — to connect to any other computer is the promise of the global computer network.

The Love Bug only affected one possible, albeit popular, computer configuration. But can it be long before the misguided come up with ways to attack all computers, or the basic Internet systems themselves? Interoperability, in the awkward phrases of the computer age, means interdependence. “The Internet and the Web have pulled us out of two-dimensional space,” wrote Tim Berners-Lee, the mathematician who invented the World Wide Web, in his book, “Weaving the Web.” “They’ve also moved us away from the idea that we won’t be interrupted by anybody who’s more than a day’s march away.”

Just a hunch, but the vast majority of people buying computers aren’t prepared for a virtual onslaught and don’t much think about it. They want to tap into the huge amounts of information on-line; communicate instantly and provide service or products of their own. They think, perhaps, the countless number of newly minted millionaires in Silicon Valley will come up with something soon to make viruses and worms as archaic as the Black Plague.

It is a level of trust that is, so far, unwarranted.