ARTICLE: Iran Agrees to Send Enriched Uranium to Russia, By STEVEN ERLANGER and MARK LANDLER, New York Times, October 1, 2009

The key bit here:

Iran's agreement in principle to export most of its enriched uranium for processing -- if it happens -- would represent a major accomplishment for the West, reducing Iran's ability to make a nuclear weapon quickly and buying more time for negotiations to bear fruit. If Iran has secret stockpiles of enriched uranium, however, the accomplishment would be hollow, a senior American official conceded.

Naturally, I think Iran has secret stockpiles of enriched uranium--hence the offer. But the "reduction" argument is valid: I don't think Iran wants a big bomb supply. I think it wants the world to be unclear if it has several and to know for sure that it has the break-out capability much like Japan--an argument of mine that goes back years. My point: there is nothing irrational regarding Iranian behavior on this subject.