When safety measures make us unsafe: how everything from seatbelts to bank deposit insurance can backfire.

• Author: Molotch, Harvey
• Position: Foolproof: Why Safety Can Be Dangerous and How Danger Makes Us Safe - Book review

Foolproof: Why Safety Can Be Dangerous and How Danger Makes Us Safe, by Greg Ip, Little, Brown, 326 pages, $28

SOMETIMES OUR efforts to be safe have the opposite effect. Bike helmets may seduce riders into taking chances they otherwise would not. So they die. Better to think riding a bike is really dangerous: That leads to more caution, and more lives saved. Same with snow tires--having them lessens anxiety, and presto, careless maneuvers are more likely.

In Foolproof, reporter Greg Ip of The Wall Street Journal takes up many examples of unintended effects. Seat belts, antibiotics, river dams, antilock car brakes, fire prevention, saving for a rainy day--all good things that, I fear to say, have at least the prospect of built-in danger.

But some safety measures do work, a lot of times dramatically or at least pretty well. The book's subtitle tells us that safety "can be" dangerous, not that it will be dangerous. This leads to the inconvenient necessity of rational discrimination on a case-by-case basis. Kids driving without seat belts on a Saturday night are a self-destroying menace in a way middle-age women on a Tuesday morning are not. We need, as Ip declares (and delivers), to examine the relevant "history and evidence with an open mind." Even when much of the story is well-known, Foolproof gives us further details that clear up old questions--and sometimes, alas, raise new ones.

Fire prevention is a good place to start. Smokey the Bear had a myopic view of the health of forests--no fires, no way, no day. Some plant species, however, need fire to reproduce; it's part of their nature. Mature trees, Ip explains, survive forest fires because their crowns are above the intense heat churned up below. What does them in are stands of adjacent young trees that provide a ladder for flames to climb to their crowns. Regularly occurring, and thus smaller-scale, fires would have destroyed those young trees. Such fires would also have taken away the heavy kindling that otherwise accumulates on the forest floor. In the longer term, and contrary to Smokey, nobody can prevent forest fires. It is often good to let nature run its course.

Another charge against Smokey: "His campaigns against fires lull people into building houses where they should not go, as do all the paraphernalia on standby to stamp them out. Among other troubles, this shifts costs to insurance companies (who are slow to get the message and raise premiums), to public agencies that deploy...