Can ISIS make a comeback?

 Wall Street Journal:

Fears Grow of Islamic State’s Re-Emergence in Syria

U.S. steps up strikes from desert bases against an enemy it defeated half a decade ago

Islamic State militants were already resurgent last year in parts of Syria and Iraq. Then in December, the Assad regime collapsed, furnishing them with fresh supplies of weapons from stocks abandoned by the Syrian army.

The group that once terrorized the Middle East and inspired attacks elsewhere in the world is looking to exploit Syria’s uncertain future to rebuild its influence—half a decade after U.S.-led forces broke its hold on swaths of territory and millions of people.

In a sign of its persistent appeal, a U.S. Army veteran in a pickup flying an Islamic State flag drove through a crowd of people early on New Year’s Day in New Orleans, killing 15 and injuring 30 in what authorities called a terrorist attack. It wasn’t clear what connections, if any, the assailant might have had to the group, but analysts have warned of lone-wolf incidents and copycat attacks.

The fight against the remnants of Islamic State had until recently happened in the shadows, with hundreds of U.S. Special Forces based in Syria’s hinterlands working with Kurdish militias to carry out airstrikes and raids. The U.S. has since ramped up its attacks, including in areas where the airspace was previously controlled by the government of Bashar al-Assad and its Russian allies, military analysts say.
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The Islamists persist despite their losses in battles with US forces and US allies.  The US launched its attacks on the group after the attacks on New York and Washington on 9-11.  In recent months the loss of control by the Syrian dictator has apparently opened the door for the terrorists.