She said that as fighters, the Islamic State militants have "mostly been a disappointment."

"Their numbers don't seem that big and they're eager to run away," she told INSIDER in an email. "I suspect most of the experienced fighters have been consolidated in Mosul and Raqqa, and that's where the big fights will be."

She said that ISIS has successfully made themselves seem bigger and scarier than they are in reality through social media.

Although the group recently claimed responsibility for terrorist attacks that killed hundreds in Paris, Beirut, Baghdad, and Ankara and over the Sinai Peninsula, its promise of statehood is quickly diminishing, The New York Times reports.