Back around the turn of the century, when the biggest business story going was the Microsoft antitrust trial, I found myself one afternoon in conversation with Bill Gates on the topic of his legacy. Even more than most multibillionaires, Gates had always, it seemed to me, been prone to caricature: first as the original golden geek, a brilliant, nonthreatening nebbish; then as the far-seeing avatar of the PC revolution; and now, with the government threatening to break his company into pieces, as the postmodern robber baron, the New Economy’s John D. Rockefeller. And so I asked Gates if he thought about how history would judge him. “No,” he said flatly. “I’m sure history will simplify things by taking a few people and talking about their role in personal computing. But it doesn’t matter; it doesn’t motivate me. If we’re all forgotten or remembered, it doesn’t change what we do every day—but that hasn’t really changed in the last 25 years.”

The memory of Gates’s comments came flooding back to me the week before Christmas, when a pair of events thrust him and his company into the holiday headlines. The first, of course, was his selection by Time—along with his wife, Melinda, and U2’s front man, Bono—as one of its Persons of the Year, a selection based entirely on his charitable endeavors. And the second was the decision by AOL to abandon, at the eleventh hour, a planned corporate commingling with Microsoft, and instead climb into bed with Google, Gates’s bête noire du jour.

Coincidence? Sure. But the contrast is revealing nonetheless. By all accounts, Gates has emerged as the most influential philanthropist on the planet; with a $29 billion endowment, his foundation is setting new standards for both generosity and rigor in tackling an assortment of the world’s most dire maladies, from malaria to HIV. At the same time, Gates no longer cuts the profile he once did as a high-tech titan. While he’s still respected, he’s no longer scary—and the totemic company he built from scratch seems increasingly ordinary, even irrelevant.

Thus will 2005 be remembered as the year Gates’s public persona shifted once again: from Bill the Software Barbarian to Bill the Bighearted Benefactor. But this time the shift is about more than Gates’s image. It’s about the changing nature of his power—and the fact that he’s playing for history now. And while Time’s cover story was conspicuously free of any robber-baronial parallels, Gates’s commendable burst of noblesse oblige has set him up, today more than ever, as the inheritor of the two-sided mantle once donned by Rockefeller, Carnegie, and Vanderbilt.

Gates, naturally, would recoil at the comparison—and yet in private moments he must be aware of how snugly it fits. Despite once claiming that neither he nor Steve Jobs “will merit an entry in a history book,” Gates has never suffered from a lack of self-regard. As far back as 1993, after Bill Clinton’s election, he informed a friend at a dinner party, “I have as much power as the president.” (Melinda, evidently aghast, kicked him under the table.)

Indeed, it strikes me that it must be faintly galling to Gates that he hadn’t been named Time’s Person of the Year before now. (Especially since the honor was bestowed, at the height of Microsoft’s hegemony in the nineties, on both Intel founder Andy Grove and Amazon.com CEO Jeff Bezos.) Gates, in fact, was the in-house front-runner in 1996—until a burst of late-year publicity around progress in treating HIV prompted Time’s then–managing editor Walter Isaacson to choose aids researcher Dr. David Ho instead. And Gates would have been an equally natural pick in 1997—until that fall, when the Department of Justice launched its historic lawsuit against Microsoft.

For much of the next four years, the company was consumed with its battle against the Feds. And Gates was subjected—or, more accurately, subjected himself—to a brutal drubbing in the court of public opinion. But this was also the period in which Gates took up philanthropy in earnest, abandoning his previous inclination to wait 20 or 30 years, until after he had retired, to begin the process of dispensing the bulk of his massive fortune (as he had indicated he would). “When you have the resources that could make a very big impact,” he said later, “you can’t just say to yourself, Okay, when I’m 60, I’ll get around to that.”

Inevitably, some of Gates’s critics suspected that he was attempting—as Rockefeller biographer Ron Chernow once wrote about one of the objectives behind the philanthropic activities of Standard Oil’s chief—to “fumigate his fortune.” (Not to mention fumigating Microsoft in its moment of legal jeopardy.) At the time, I put the question of Gates’s motives to his friend Patty Stonesifer, who had taken on the position of the Gates Foundation’s CEO. “Why is he doing this?” she said. “Frankly, who cares? If our money helps speed the development of an effective aids vaccine by a few years, it would mean saving tens of millions of lives.” Placed in that context, Stonesifer concluded, Gates’s intentions were irrelevant. “When people impugn his motives, Bill just says, ‘You’ve got to take the long view—history will get this right.’ ”

In 2000, Gates stepped down as CEO and assumed his current title: chairman and chief software architect. The official line at Microsoft was that he was reenergized, reinvigorated, up to his elbows in the company’s future, shepherding new products and formulating new strategies. But by the time I saw him a couple of years later at a conference in California, it was clear to all in the auditorium that software no longer got Gates’s juices pumping the way his work at the foundation did. Technology questions were answered quickly, without passion, whereas questions about global health elicited lengthy disquisitions full of detail and emotion. The way he talked about wiping out malaria was how he used to talk about wiping out Netscape.

Ever since then, Microsoft has noticeably been drifting. Not that the company isn’t still enormously profitable and doesn’t exercise terrific clout in the markets where its products are entrenched. But there’s no escaping the impression of an outfit beset by strategic blurriness and lumbering middle age—or disguising the fact that, despite countless fervent if flailing efforts, Microsoft is getting its ass kicked handily in the race to rule the Internet. Here you have Yahoo, trouncing MSN as an all-purpose Web portal. And there you have Apple, crushing it in online music. Here you have poor, doom-struck AOL, beating it in e-mail and instant messaging. And there, most glaringly, you have Google, whipping Gates’s company in Web search and advertising—and the crucial competition for top-drawer talent.

Nowhere is Microsoft’s decline more keenly felt (or warmly welcomed) than in Silicon Valley. “Ten years ago,” observes Joe Kraus, one of the founders of Excite, “if you were starting up a company, you assumed that Microsoft already had ten engineers working full-time on the same thing, and they were probably going to eat your lunch. But you don’t say that anymore about Microsoft. You say it about Google. They’re the 10,000-pound gorilla now.”

For Gates, then, losing out on the AOL deal to Google—a deal he’d personally been involved in negotiating, courting Time Warner CEO Dick Parsons at last year’s Allen & Co. summer retreat in Sun Valley—would have been all the more painful for what it represents. For 25 years after Microsoft’s founding in 1975, Gates labored furiously to see that his company would escape the fate that befell his archrival IBM, along with every other technology outfit that rose to dominance in one era, then slid into senescence in the next. Yet now he sees his precious baby veering dangerously in the direction of becoming the new Big Blue: large, profitable, and stuffed with happy employees, but feared or followed by no one. Unimportant, in a word.

Rockefeller’s life traces essentially the same arc on which Gates appears to be traveling.

Gates’s consolation is that his opportunity to be a transformational figure isn’t lost with Microsoft’s abeyance. This is not a trivial thing. Gates has already changed the world once; now, through his foundation—which is not only disgorging a gusher of funds but inventing a new model for philanthropy, driven by statistics, leverage, and an insistence on accountability—he has a chance to do it again. And as Bono told Time, “The second act for Bill Gates may be the one that history regards more.”

Which brings us back to J. D. Rockefeller. Now, Gates and Rockefeller are very different animals in many respects—starting with Rockefeller’s devout Baptism (Gates has never emitted any visible sign of believing in any omnipotent being other than himself). But with respect to philanthropy, Rockefeller’s life essentially limns the arc on which Gates appears to be traveling. After a career in which he was accused of a panoply of predatory behavior, Rockefeller retired in 1910—a year before the Supreme Court voted to break up Standard Oil, but, interestingly, a few years after its market share began to shrink—and devoted himself to good works, notably the founding of the Rockefeller Foundation, which was as much an innovator in its time as the Gates Foundation is today. By the time of his death, in 1937, Rockefeller had attained an image in the public mind of a kind of secular saint. Today he’s remembered as much for his acts of charity as for his earlier acts of commercial treachery.

As precedents go, it’s a heartening one for William Henry Gates III. Although, as I said, I’d wager big money that he doesn’t see it that way. Above all, Gates would probably object that there’s no way Microsoft is in danger of being rent asunder these days. And he’d be dead right—because the company, by and large, has ceased to be a menace to anyone. That itself might pain Gates to hear, though in truth he should see it as a blessing. For if Microsoft were still the Beast from Redmond circa 1997, there’s not a chance in hell he’d be a Person of the Year, let alone one that Time would have ever seen fit to label a “Good Samaritan.”

E-mail: jheilemann@gmail.com.