IN A LITTLE-NOTICED side effect of the war on terrorism, the military is edging toward a sensitive area that has been off-limits to it historically: domestic intelligence gathering and law enforcement. Several recent incidents involving the military have raised concern among student and civil-rights groups. One was a visit last month by an Army intelligence agent to an official at the University of Texas law school in Austin. The agent demanded a videotape of a recent academic conference at the school so that he could identify what he described as "three Middle Eastern men" who had made "suspicious" remarks to...