CHRISTOPHER LIVESAY:

Once a jewel of the Roman Empire, Libya's port city of Sabratha is home to an ancient amphitheater that more recently was the backdrop of a city overrun by terror. ISIS took control in 2015, and asserted its authority by beheading 12 members of the security forces, and setting up its own checkpoints. Today, the tables are turned. Libyan police loyal to the government in Tripoli now check for ISIS militants. One of them tells me the city is safe, but checkpoints are common targets for terrorist attacks, and any one of these vehicles could be packed with explosives. Police are also looking for stolen fuel – ISIS is known to smuggle it from Libya's vast reserves and use the profits to fund their attacks. Libya's spot on the map makes it particularly attractive to terrorists. Parts of the sprawling country three times the size of France are ungoverned. And the country has largely uncontrolled borders, offering several gateways for action says Carnegie Endowment Senior Associate Frederic Wehrey.