The two Benjamin Friedmans of Cambridge, Mass.

It's important to keep your Benjamin Friedmans straight.

Benjamin M. Friedman, who must be in his early 60s, is an eminent professor of economics at Harvard and a frequent contributor to the New York Review of Books and, yes, the Atlantic. He has helped lead us to clear thinking about economics and related political/cultural matters.

Benjamin H. Friedman, who must be in his late 20s, is a PhD candidate at MIT who has done some very valuable work at a tender age. An essay three years ago in MIT's publication "Breakthroughs" was one of the earliest attempts, anywhere, to say: wait a minute, how much are we willing to give away or throw away in the name of being "safe"? (The essay is "Leap before you look" and is on page 29 of this 6MB PDF file.) The logic is now familiar: just as a person can avoid many "risks" by never leaving the house or answering the phone, so a society can be "secure" by keeping everyone under scrutiny all the time. The only problem is, what makes life worth living disappears. Again, many people say this now: fewer did in 2004.

As far as I know, the two Benjamins are not related.

Benjamin "MIT" Friedman has recently pointed out another "leap before you look" step in the quest for security:the impending Congressional mandate, reported here by our sister publication Government Executive, to require the government to scan all cargo containers before they are shipped to the United States.

Recall from this Shenzhen story that just one port in China sends out a shipping container every second, 24 hours a day, every day of the year. Does anyone actually think that all of them are going to be scanned or X-rayed? And all the others, from every other port in the world? With what machinery? And what work force? Paid by whose tax dollars? And with what effects on the flow of goods that everyone takes for granted -- on the Chinese side and the American alike.

Yes, relying on the current system of testing a small sample of containers -- or "profiling," to concentrate on ports and shippers of highest risk -- opens the possibility that some container, from somewhere, will be filled with a bomb. Similarly: our current system of allowing people to drive cars without being stopped at roadblocks every two miles opens the possibility that someone will drive past the U.S. Capitol with a dirty bomb in the trunk. And our current system of not inspecting every car at the mouth of a tunnel opens the risk....

There are risks in life. The essence of security is maintaining a sense of priority and proportion. That gets harder each time someone proposes something that is clearly insane, like the idea that you actually could inspect the hundreds of millions of containers moving around the world, without bringing on a second Great Depression in the process.

Hey, there are more or less that many cars in America. Why don't we warm up by inspecting every single car before every trip? With a Congressional mandate it should work fine.