I hear the Secretary of Energy has halted all work at the national laboratories on Iran.

Why?

There is no public explanation, but speculation centers on the role of DOE analysts in making the Administration look liars on the issue of those infamous Iraqi aluminum tubes

At the time, the Bush Administration appears to have engaged in a campaign to silence DOE employees. As David Albright wrote:

The administration was forced to admit publicly that dissenters exist, particularly at the Department of Energy (DOE) and its national laboratories. This dissent is significant because the DOE has virtually the only expertise on gas centrifuges and nuclear weapons programs in the United States government.

This about that. Having bungled the intel on Iraq, the Administration is now shutting down the “the only expertise on gas centrifuges and nuclear weapons programs in the United States government” as the United States faces hard choices abuout the Iranian nuclear programs. I guess John Bolton already knows the answer.