The new book by the former counterterrorism official says that federal officials thought Boston Harbor may have been target on 9/11. Evidently some of the al Quaeda terrorists entered the US on liquified natural gas tankers and that some in the government thought the tankers may have been rigged to explode, which would have been a major explosion, like a min-nuke.
Now, I don’t necessarily give credence to Clarke. There are too many holes in his other stories, but if this is true, it’s still kind of scary to contemplate what might have happened. Wow.