When the new school year begins, Deena Esteban will not be among the legions of educators welcoming students back to class. That's because Mrs. Esteban, a 43-year-old art teacher in Prince William County, Va., lost the job she loved after being convicted of a felony last fall. Her crime? Bringing a gun to school. Mrs. Esteban's story is a textbook case of zero-tolerance tyranny. Teachers are the forgotten casualties of the education establishment's absolutist war on guns. Mrs. Esteban had never been in trouble with the law. The married mother of two owned a .38-caliber revolver for self-defense and -- ...