While I fully support the option of permitting the flight crew to carry sidearms, the primary responsibility for armed security in-flight needs to rest with full-time security personnel.
A heavy transport demands a flight crew that devotes most of their working time to training for their flight crew duties — when not actually performing them. If someone thinks it's realistic for a flight-crew to devote an extra 2-3 hours per day to an elite-level PT regimen, another 2-3 hours on unarmed and impact-/edged-weapon techniques, and the balance of each training day boning up on Battle Drills (mostly live-fire), he's sadly mistaken.
Factor in an additional training budget that allows 5000-9000 rounds of ammunition per crewmember per annum and a new weapon per crewmember per month — they wear out that quickly if you're training properly!
To expect a flight-crew to function as an in extremis counter-hijacking team in addition to their usual duties is unforgivably stupid.
In the mil/LE special-ops community, what is commonly known as the "tubular assault" (a/c, bus, train takedown) is one of the most difficult Close Quarter Battle problems that can present. Introducing innocent bystanders into the equation — co-mingled among and between the various belligerents at nearly point-blank range and under extreme duress — demands precisely the standard of CQB training to which I alluded above. To further complicate the issue, most systems of civil jurisprudence of which I am aware do not recognize the concept of "collateral damage" when pax start dying from rounds off-target, whether due to substandard marksmanship or overpenetration!
The standard this task demands can only be achieved and maintained by personnel whose full-time occupation consists solely of security — and specifically, counter-hijacking — duties. To rely upon any lesser standard from an armed in-flight security resource is legally dubious and morally unconscionable.
That said, I'll drift off-topic for a moment and add a personal footnote:
Given the current situation cause by this week's developments, my plans for completion of my FAA CPL-ASEL/RH (just a few hours left!) are undoubtedly going to be on an indefinite hold now. As a National Guardsman — ex-paratrooper turned Cavalry Scout team-leader — I anticipate my unit will likely be called to active duty at some point in the near future. Until it's over, the C172 and R22 remain stabled in exchange for an HMMWV w/Mk-19 and a nice load of other assorted nasties.
May those responsible for Tuesday's atrocity become the owners of gaping new ässhøles — forcefully ripped — speedily and soon.
PS: The support of those from the European side of the Pond is duly noted and appreciated!