Carrier Groups

Remember those aircraft carrier groups stationed in the Persian Gulf? It was widely assumed that you would need three to attack Iran. The Pentagon insisted that there would only be three in the Gulf for a brief time, one replacing another. The news reports I've read said exactly that.

Until today.

Barnett Rubin who broke the story about plans for the U.S. to attack Iran says there are three carrier groups still in the Gulf.

Is this true?