White House ethics counsel Norm Eisen’s conclusion that John Brennan should participate in the reviews of the attempted bombing of Northwest flight 253 is interesting.

Currently serving as assistant to the president for homeland security and counterterrorism, Brennan formerly worked at the Analysis Corp., a contractor that helped develop the watch-list system, one of many security measures that did not prevent the attacker from boarding a flight into the United States.

In my review of some of the security systems involved in the failed attack, I agreed that watch-listing failed, but I am at a loss to imagine how it could succeed.

On the merits of the ethical issue, Eisen cites Brennan’s long experience and the importance of this matter to national security as reasons that Brennan should be granted a waiver from the general two-year ban on political appointees having involvement in matters involving former employers and clients.

But these factors cut equally well, if not better, in the other direction: Long experience can bring a person too close to the problem to see solutions. And national security is too important to let insiders review their own work.

I have no reason to doubt his good faith, but Brennan’s substantive judgment is likely to be obscured by familiarity with, and sympathy for, watch-listing. He will be unlikely to give sufficiently close examination to the question whether it provides security value given its failure here and its costs in dollars, constitutional principles, and privacy.

Kudos are due the White House and Norm Eisen for posting the ethics waiver on the White House blog. Brennan’s assessment of watch-listing should get similar airing so that the public can review his work aware of his probable sympathies. An outside review may lose something in inside knowledge, but make up for it with gains in substance and credibility.