WASHINGTON — The recent arrest of a Palestinian man from Florida has convinced U.S. officials that a network of al Qaeda operatives exists in the United States, CBS reported on Thursday. It said Adham Hassoun, arrested earlier this month, was an "important link" to accused al Qaeda member American Jose Padilla, as well as other groups based in the United States who may be awaiting orders for future attacks. "A number of people are under surveillance. None is believed to have had a supporting role in the Sept. 11 attacks. Some may have been slated to assist Zacarias Moussaoui," it...