Visiting Syria

Why is visiting Syria now a crime?  Apparently the Turkish police have arrested nine Brits who wanted to enter Syria -on what possible basis in  law I wonder where the arrests made? They had committed no crime in Turkey. Now I actually want to visit Syria.  Everyone I suspect has some 'wonder of the world' that they want to see before they die and mine is the great castle of the knights of St John of Jerusalem- Krak des Chevaliers.  It may - at the moment - be a bit risky to visit this fantastic monument to the Crusader - but so what - it is my life - if I want to risk it it is my affair. Equally I cannot see what business it is of this government or any other stopping people who want to go and live in Syria from doing so.

Admittedly they may be going to join the extremists but that is their choice - personally I would lay on free flights from London airport to anyone who wanted to go and fight for ISIS though there would be one condition attached - give up your passport and British citizenship to qualify