Not that bold a move because Thomas cook is a charter operator. Big deal, flights are always sold out (so not a big risk, its the low load flights that were targeted before) and as a charter airline you aren't selling direct tickets on the flight exactly but with in an interim buffer (you really don't know who you are flying when you book a package tour). Makes them extremely unuseable by a terrorist and they had virtually no chance of having a skymarshal on theplane in the first place because there would be no threat...
Lots of bluster there, but no risk because there will be no threats so no canceled flights. Or even better, since they subservice (wetlease) all the time, if they get a threat, flight still goes, just operated by another charter operator with skymarshal onboard. The only part that gets canceled is the TCA crew and plane. Pax will never know...
For BA, it will be a different can of worms and the question will be do they want to live with the canceled flights. There scope clause won't allow subservice so the only choice would be to cancel. That seams to be the compromise. Governments that have opted out, have agreed to cancel flights if there is a perceived threat against them.
It gets down to whether you think canceling the flight is the answer. Interestingly when the decision was made to cancel the flights, suposedly the "Wife and Children" test was used. (Would you put your wife and children on these flights) If that is the criteria they really used to cancel the flights, I guess I can't fault them. As a check airman that is the criteria I would use when signing a guy off...
Cheers
Wino