Now this is just me speaking...
I am a commercial pilot and I spent 20 years in the military as well, 15 of those years was as a UH-60 pilot. I also flew armed. As a pilot I would be more concerned about getting the aircraft on the ground than trying to fight some one off. I would rather have my crew (flight attendant, air marshall) fight off the attacker while I am putting the aircraft on the ground. As we used to say in the Army when in an emergency "Fly the Aircraft."
Thats just me and I am just a helicopter pilot... we are different than those civilian commercial airline pilots so we think differently.