As expected, September 11 has prompted an expansion of law-enforcement powers at almost every level. And who would have it otherwise? For those of us who live and work in Manhattan, 9-11 was not a single horrific day but an extended nightmare. For weeks, kiosks, store windows and parks displayed fliers by the thousands, pleading for information about loved ones still missing. National Guard units seemed to be everywhere. Day after day, the air -- gray and acrid -- carried the smell of burning flesh.