All you gun fanatics are missing the point: The authorities should make a real effort (not a token one like nowadays) to keep terrorists from getting on board in the first place.
This gun program is just window dressing; "look all you voters, we are being tough on terrorism. We keep you safe and ignorant". Yeah right.
Te next step will be issuing parachutes so the pax can get of a hijacked plane. And I'm sure the politicians will call it something very impressive..