The top American commander in the Persian Gulf told Congress on Thursday that the Iraqi insurgency has not grown weaker over the past six months, despite a claim by Vice President Dick Cheney that it was in its “last throes.” Gen. John Abizaid’s testimony came at a contentious Senate Armed Services Committee hearing at which Defense Secretary Donald H. Rumsfeld clashed with members of both parties, including a renewed call by Sen. Edward M. Kennedy of Massachusetts for him to step down. Full Story