Unless, of course, the whole notion that Sunnis and Shia won't work together is pure rubbish.
And this gives more reason to be tough on Iran:
One of two known Al Qaeda leadership councils meets regularly in eastern Iran, where the American intelligence community believes dozens of senior Al Qaeda leaders have reconstituted a good part of the terror conglomerate's senior leadership structure.
That is a consensus judgment from a final working draft of a new National Intelligence Estimate, titled "The Terrorist Threat to the U.S. Homeland," on the organization that attacked the World Trade Center on September 11, 2001. The estimate, which represents the opinion of America's intelligence agencies, is now finished, and unclassified conclusions will be shared today with the public.
The classified document includes four main sections, examining how Al Qaeda in recent years has increased its capacity to stage another attack on American soil; how the organization has replenished the ranks of its top leaders; nations where Al Qaeda operates, and the status of its training camps and physical infrastructure.