Turn on a football game, and you'll see cheerleaders with seam-popping breast implants, aging sportscasters with suspiciously tenacious hairlines and commercials for pills that promise Olympian erections. Turn on the news, and you'll hear about how athletes have got the notion that it's O.K. to use artificial substances to improve their bodies. Appalling! Where would they get an idea like that?

On its face, the baseball steroid scandal is simple. Athletes who break the rules to win are cheaters. But ask why we have the rules in the first place, and you have to confront a basic irony. We decry performance-enhanced sports. Yet we live performance-enhanced lives.

We all know about Hollywood celebrities who get plastic surgery to extend their careers. (You want to see performance enhancement in sports, look courtside at a Lakers game.) But plastic surgery has become positively democratic. Businessmen get nipped and tucked to win promotions; other people, just to look hot. And there are plenty of other ways that we augment nature, medically, technologically and financially. The elderly can extend their sex lives beyond what God and their grandchildren imagined. Kids take expensive prep courses to ace tests that are supposed to measure inborn aptitude. Short but healthy children are given human growth hormone for their self-esteem. Adults take Ritalin to sharpen their senses. Pop singers have their vocals, ahem, "sweetened" with additional recorded tracks. Yet no one is threatening legislation against Ashlee Simpson.

So why are steroids the exception? One obvious answer is that sports are supposed to be fair in a way that life is not. But sports are full of institutionalized unfairness—ask anyone who's ever rooted against the Yankees. Olympic runner wins a gold medal because of blood doping: Cheater! Olympic team wins dozens of medals because it has tens of millions of dollars for training: U.S.A.! U.S.A.! U.S.A.! In the steroid debate, what's often cited is fairness, not to current players but to the records of retired and dead ones. Yet middling athletes of today routinely outdo greats of the past thanks to legal advances in everything from nutrition to sports medicine to biodynamics to equipment. If Roger Bannister had the advantage of competing today, wouldn't he run better than a mere 3:59.4 mile?

Yes, but steroids are far more dangerous than, say, carb loading. That justification would be far more convincing if there were any evidence that fans and teams otherwise give two snorts about athletes' health. But that wouldn't explain how we tolerate, for example, football linemen larding up to heart-straining proportions and players hobbling themselves for life by "playing through the pain" (i.e., getting taped and numbed by the team doc). Or jockeys nearly killing themselves to drop weight. Or the very existence of boxing.

Of course, tainted Yankee Jason Giambi at least is an adult; teen athletes, however, have started using the same drugs the pros do. Again, setting a good example for kids is a noble argument—but one that society hardly heeds otherwise. If steroid scold John McCain were a woman, he might be pushing laws against plastic surgery among pop starlets, the better to save girls from deadly eating disorders. President George W. Bush denounced steroid use in the State of the Union. "It sends the wrong message—that there are shortcuts to accomplishment," said the Yale legacy student.

In the end, the steroid controversy may be less about what we want for athletes or children than about what we fear for ourselves. The performance enhancement of society promises to get only more radical, especially as genetic engineering grows more advanced. When people of means can buy sharper brains and stronger bodies for themselves or better genetic profiles for their kids, juiced-up athletes will be the least of our ethical worries. If Giants slugger Barry Bonds deserves an asterisk next to his home-run records, maybe we will deserve asterisks next to our salaries, our sexual conquests and our kids' SAT scores.

Our new power to transform ourselves raises the question of whether we are changing from nature's creation into man's invention. So we ask athletes to maintain an authenticity that we don't want to—to be museum pieces of purity. Is that hypocritical? Yes, because the fan-athlete relationship is inherently hypocritical: fans want sports heroes to be more admirable than the rest of us. We used to worship athletes for being mightier, faster, greater than we could imagine. The day may come when we gather in stadiums—with our bought-and-paid-for brains, bodies and libidos—and cheer on players for making do with less.