Richard Drew, AP
British Prime Minister David Cameron

British Prime Minister David Cameron deserves credit for showing the rest of the world that governments aren't taking their charge to protect the general welfare of their citizens seriously without launching an attack on the scourge of pornography.

Cameron correctly said pornography is "corroding childhood." It changes the way young people develop attitudes toward the opposite sex. Its growing influence in the world is corroding the value of marriage and family and diverting natural affections toward selfish gratification. American politicians should be eager to follow Britain's lead.

Cameron announced a new program this week, under which everyone with an Internet connection automatically will have filters against pornographic material installed and will have to take steps in order to opt out. The possession of so-called "extreme pornography," in which simulated rape is portrayed, will be outlawed. The government will create a list of "abhorrent" search terms, which it will use to identify potential pedophiles who are searching for illegal material. Police will use a single database of illegal child images to help identify and arrest perpetrators.

The naysayers have let loose with their predictable barrage. The measures won't work, they say. Pedophiles are smart enough to know how to evade filters using a proxy or VPN, similar to how people under regimes in Iran and China circumvent government Internet controls. Some even claim an increased access to pornography has reduced violent crimes against women, comparing a declining rate of rape in the United States with increases in India, where strict government controls against pornography are in place.

The statistical analysis is lazy, at best. It doesn't account for any of a host of other variables that may account for fluctuations in crime rates. Murder rates are down in the United States, as well, despite strict laws against killing. The other claims may hold some validity, at least on the surface. Savvy computer users will find ways around laws, just as criminals always look for ways around any laws that stand in their way. But the critics greatly underestimate the way free governments can change cultural expectations.

Forty years ago, many of the same arguments could have been made against a ban on cigarette advertising. At the time, smoking was common, despite medical evidence of its harm. But the ban succeeded in making smoking culturally unacceptable, which led to laws and ordinances prohibiting it in public places. Today, only 18 percent of Americans smoke, according to the Centers for Disease Control and Prevention. That's down from 40 percent or more in the early 1970s.

There is every reason to believe a general ban on pornography would, over time, make viewing such material socially unacceptable and reduce the overall rate of consumption. It would be unrealistic to think it possible to eliminate pornography all together, just as it may be impossible to eliminate all cigarettes. But a significant reduction would be enough to save much of the rising generation from harm.

Studies have shown the sexualization of young girls, in particular, leads to problems with academic performance, self-esteem and proper socialization among maturing young women. A report by the American Psychological Association, titled "Report of the APA task force on the sexualization of girls," compiles an impressive array of scholarly studies that makes this clear. Pornography also changes the way young men perceive the opposite sex, as well as their expectations of intimacy.

Critics may howl about rights of expression, but the evidence is clear. Cameron's bold move is a positive step for Britain. It should be mimicked worldwide.