Liberal caterwauling about FFL availability will never be rational, but we should be aware of the talking points they use when confronted.
I never heard or read this little "gem", and I'm not sure, depending on where I read it, if I'd believe it. It sounds like the other, post-911 scare-the-public-into-more-gun-control propaganda, along the lines of the supposed words in the Al Qaeda training manual found (fellow Jihadists - you must buy your guns at American gun shows - or something to that RIDICULOUS effect), and the propaganda concerning terrorists wanting to buy .50 cal SEMI-auto firearms to attack our infrastructure and planes.
True or not though, you help make my point.
What did those terrorists do with that FFL, if they actually had one (they sure didn't need it to buy box-cutters)? It's likely they did nothing that put any Americans in danger on any scale to speak of, and certainly not much more than your average street gang that can acquire guns in more creative ways than can be imagined.
I think we have MUCH more to worry about as far as terrorists getting and using bombs & missiles (like the planes that flew into the towers), and weapons grade bio and chem weapons.
FFL or no FFL, terrorists, like criminals, are going to get firearms, but they are looking for MASS casualties, with the resultant panic and fear instilled in the general populace.
Besides, they learned YEARS ago, that attacks on Israelis with mere firearms, even fully automatic weapons, does not get the desired result. They now use infinitely more effective means and tactics like human homicide bombers.