AT& T, IBM, Intel, Microsoft . . . Google?

For example, if you're looking for an Internet social network, you probably want the one that has the largest number of your friends and colleagues. If you're shopping for computers or software or computer chips, you'll probably prefer the ones compatible with everyone else's or with those you already have. Because of these tendencies, the companies with a head start in developing the biggest network of users usually win, even if competitors come along offering superior products or slightly lower prices.

[an error occurred while processing this directive]

Google has all of these advantages.

Because it jumped into the lead in the Internet search business, largely because it had the better product, Google has the biggest bank of search history to use to constantly improve the quality of its algorithms. Better quality, in turn, generates even larger market share. As a result, Google accounts for about two-thirds of Internet searches done in the United States, with its market share increasing daily.

Internet searches, of course, are free. But Google's other genius has been in its ability to turn its search dominance into cash. The logic goes like this:

Because it has the most searches, Google can direct the largest number of consumers to the ads on its search pages or those its automated advertising exchange puts on other Web sites.

Because its ads generate more sales than any others, Google has been able to attract the most advertisers.

And because its advertising exchange has the most advertisers, it is able to attract the most Web site publishers.

Note that there is nothing illegal going on here. Google has become the dominant player in search and Internet advertising because it had the best product to offer to advertisers, publishers and Internet users. Just as AT&T, IBM, Intel and Microsoft did, it has won its near-monopoly fair and square.

Here's where the antitrust law comes in.

At its heart, the aim of antitrust law is to ensure consumers the benefits of lower prices and greater choice that come with competition. In most markets, that means ensuring that there are enough competitors. But in markets that tend naturally toward a dominant firm, competition comes not from a business offering the same product or service but from a new technology or way of doing business that comes along and upsets the terms of competition.

This is how MCI unseated AT&T in long-distance telephony and how Microsoft and Intel used the personal computer to challenge IBM's mainframe dominance. Today, it is how Google has used the Internet and open software to break Microsoft's hold on personal computing. And someday, a new idea will come along to supplant Google as Internet kingpin.

Nobody knows what that idea will be -- not you, not me, not Google and certainly not the government. But it is the government's job to make sure the monopolist doesn't use its advantages to eliminate the emerging contenders, either by buying them up or leveraging its existing monopoly to gain a dominant position in the next new thing.