“Chrome is not going to replace Windows. A computer requires an operating system such as Windows, Apple’s OS X or Linux to make the machine work. It does, however, have the potential to do what Mr. Gates feared: make the choice of operating system less important.”

So writes John Gapper, the fine columnist for The Financial Times in today’s paper. Chrome, of course, is Google’s new browser, which is pretty explicitly designed to be a Windows killer. As Mr. Gapper notes, that precise fear — that an Internet browser could become such a powerful platform for applications software that it would effectively take over the function of the operating system — is what caused Microsoft to start the browser wars in the 1990s, effectively putting Netscape out of business.

But it seems to me that even without the browser-as-platform, Windows is already dying a death by a thousand cuts. Yes, Microsoft still makes billions by selling pre-installed Windows via computer manufacturers. But ever-so-gradually, the Internet is upending its business model just as surely as it has upended models for the music, television and newspaper businesses. It is also true, as Mr. Gapper notes, that Bill Gates saw this coming many years ago — and sounded the alarm in a famous memo to Microsoft’s executives. But in the subsequent decade-plus, the company has been unable to keep it from happening.

Think about it: do you really care anymore which operating system you use? I don’t. For years, I owned both a PC and a Mac. I could use Microsoft’s Internet Explorer, Apple’s Safari or Mozilla’s Firefox, more or less interchangeably, to access the Internet. I could write an article on one computer, send it via an email message to the other one, and it worked just fine. Ditto for PowerPoint, spreadsheets, and many of the other applications most people use — including Apple’s iTunes. Even my teenage sons, who stuck with Windows because most computer games were written for PCs, stopped caring. They could play games over the Internet, and all the most popular games were made for the Mac as well. I’m convinced that iTunes and the iPhone are not the only reasons Mac is gaining market share. The other is that people have come to realize that they do not really need Windows anymore. Any ol’ operating system will do. The browser and the Internet have already rendered them largely irrelevant.

I’ve long believed that the key moment in the modern history of Microsoft can in the mid-1990s, when two key executives battled over which direction the company should go. Brad Silverberg argued that the company should stop trying to protect Windows at all costs, and embrace the Internet. James Allchin, who led the Windows team, said that the operating system was the company’s bedrock, and its biggest source of profits, and that the Windows monopoly had to be protected no matter what. (This battle is wonderfully recounted in David Bank’s much underrated 2001 book, “Breaking Windows.”)

In the end, of course, Mr. Allchin won the battle, Mr. Silverberg left the company — and Microsoft has been a day late and a dollar short on all things Internet ever since. The ultimate consequence of that decision may well be that Google will win the war.