If a Muslim woman, in full hijab, bypassed security by carrying a rifle to "help a passenger" how safe would you feel? Would she be sanctioned/fired for breaking regulations or would TSA be afraid of allegations of Islamophobia by groups such as CAIR? Another good question, what would stop any TSA agent, out of religious beliefs or out of greed, from smuggling another weapon, a possibly loaded weapon?
If we had Air Marshalls on every flight, ala El Al, that would be REAL security. With that action we could do away with TSA, their intrusive scanners and insulting patdowns.