After 9-11 and reinforced, armored cockpit doors, forced entry has become a virtual non issue. This security hole has long been plugged and is now dwarfed by much larger security concerns:
Shoulder fired Stinger type missles;
Remotely detonated plastic explosives in checked baggage;
Suicide bomber-passengers with undetected plastic explosives wrapped around their bodies;
Suicidal passengers spreading viruses like smallpox, or ...SARS;
Suicidal truck bombers crashing explosives ladden cement mixers through fragile airport perimeter fences...into taxiing jets....
Nothing that a pistol toting pilot could prevent.
