The Internet became a major force in everyday life in the late 1990s. Before then, porn was available in adult stores, through X-rated video rentals, and on some newsstands. But with the arrival of the Internet, porn availability exploded. It was just a click away 24-7 for free in tens of millions of homes and offices. In 1997, 16 percent of American adults used the Internet regularly. By 2005, the figure had quadrupled to 65 percent. The Internet has also made porn much more available to impressionable kids. How many kids, ages 10 to 17, have viewed Internet porn? According to a recent report in the journal Pediatrics, 42 percent.

If porn is a significant contributor to social harm, we would expect to see substantial increases in sexual irresponsibility, divorce, and rape since the late 1990s when the Internet suddenly made X-rated material much more available to those who might instigate sexual mayhem, overwhelmingly men.

Guess what. Since the arrival of Internet porn:

* Sexual irresponsibility has declined.
* Teen sex has declined.
* Divorce has declined.
* Rape has declined.

Why would social ills decline as porn becomes more widely available? No one knows. But the one thing porn really causes is masturbation. Internet porn keeps men at home one-handing it. As a result, they're not out in the world acting irresponsibly-or criminally.

I'm not arguing that porn is utterly harmless. Some men consume it so compulsively that it interferes with their lives. They need therapy. Some women become distraught when they discover that the men in their lives enjoy porn. They might benefit from couple therapy. And to the extent that porn is a sex educator, it teaches lovemaking all wrong. More about this in a future post.