Either A, or B, or C

US stops British Muslim family from boarding flight to visit Disneyland

We could just close the door to all Muslims and freak out the civil libertarians and the left.

Or we could do a lot more sweeping and intrusive snooping to keep out dangerous folks while leaving the rest alone and freak out the civil libertarians and the left.

Or we could skip it, do nothing, and agree terrorism is not such a threat we need to try to prevent it at quite any cost, by any means necessary.

No more than other forms of deadly crime.

Well, not generally, anyway.

Though it's worthwhile trying hard to stop it becoming a lot more dangerous than other forms of deadly crime.

And there was that rather astounding day in September, 2001, as I recall.

Jihaders gaining control of countries or creating their own (think of ISIS carving out a big piece of Iraq and Syria) would not be good.

I have it in mind that states might find it easier to lay hands on nukes or radiological weapons than terrorist groups or guerrilla armies.

Though one needs to remember not to create or get stuck in even more quagmires.