Nearly three years ago, Brian Morgenstern was a college dropout more or less content with his job as an assistant manager at a Mount Laurel Circuit City. Then a man dropped off a videotape, asking that it be converted to DVD. Morgenstern's life hasn't been the same since. On the tape, he saw men firing rifles and shouting "Allah akbar," Arabic for "God is great." He found the images disturbing enough that he contacted local police, prompting an investigation that culminated in Monday's convictions of five Muslim immigrants from South Jersey on charges of plotting to kill U.S. soldiers. Today,...