IS loss of border area with Turkey sharply harms group

BEIRUT (AP) – Expelling the Islamic State group from the last territory it controlled along the Syrian-Turkish border has effectively cut the militants’ supply lines from the outside world. That could affect their ability to protect their last bastions – the cities of Raqqa in Syria and Mosul in Iraq.
The area under IS control has been shrinking for months, under assault from forces determined to wipe out the self-declared “caliphate.” The fight for Mosul appears to be imminent, with U.S.-backed Iraqi forces closing in, and Raqqa will probably be in the crosshairs for an attack possibly led by Kurdish militias in the near future.
If removed from power in the territory it controls, many fear it will turn even more decisively toward terrorist attacks against civilians in the region and in the West, operating from the shadows. It that way, it will be more like the group it developed from: al-Qaida.
A look at the current battle against Islamic State:
HOW DID THE SUPPLY LINES FROM TURKEY WORK?
After the Syrian conflict began in March 2011, people could evade Turkish troops on the border and sneak into or out of Syria. Many of those crossing into Syria were jihadis from around the world joining al-Qaida’s branch. Others, mostly Syrians, could use border checkpoints. Smugglers also were active, helping people cross over.
WHY DID TURKEY ALLOW THIS, AND WHAT CHANGED?