What happened to my thread about the November 9, 2...

What happened to my thread about the November 9, 2004 Christopher Hitchens article on Slate.com? I know it was not DP (I searched), so that's not the answer. What exactly are the guidelines for deleting a thread? In light of the fact that I though my thread was relevant, appropriate and interesting I think the guidelines should be posted somewhere or e-mailed to MIFI uses.