U.S. Set for a Major Assault on Guards By MATT KELLEY .c The Associated Press WASHINGTON (AP) - Some of Iraq's Republican Guard units surrounding Baghdad have been hit so hard by airstrikes they are at less than half strength, the Pentagon's top general says. ``I imagine their morale is a little low right now because they've lost a lot of their force,'' Gen. Richard Myers, chairman of the Joint Chiefs of Staff, said Sunday. ``Their fighting capability is going down minute by minute, hour by hour. There's not going to be much left to fight with.'' In street-by-street fighting...