As to Reid's decision to close the Senate, Waas reports here:

Whether there was a political motive to what Reid today, the truth of the matter is that many Senators felt like they have been lied to, or as one senior staff aide told me, they "felt rolled in an alley"-- in being stymied, as they view it, in conducting an inquiry into the most fundamental issues as to how a country went to war, and whether Congress has a right to oversee whether the administration misused intelligence to make the case.

Murray recounts the factors that led Reid to close the Senate yesterday - and to consider pressing now for the Select Committee. He cites the lack of agreement over the completion of Phase II of the Senate Intelligence Committee investigation; the discovery by Senators and their staff, from Murray's previous article, that Cheney, Addington and Libby were personally involved in withholding the documents from the committee; the indictment of Libby alleging that he played a role in leaking Valerie Plame Wilson's identity; the elevation of Addington to Chief of Staff; and Special Counsel Patrick Fitzgerald's statement that while he could not turn over documents to the Senate Committee due to grand jury secrecy rules, he wouldn't advise them not to conduct their own investigation.

Waas relates that Sen. Jay Rockefeller prodded Reid to close the Senate.

As vice-chairman of the Senate Intelligence Committee, Rockefeller has been praised by Republicans for his bipartisan approach, and has at times even privately drawn the ire of Democrats.

Here is Rockefeller's statement as to why he encouraged Reid to take the Senate into executive session:

"An iron curtain came down upon us....The very independence of the United States Congress as a separate and coequal branch of the government has been called into question."