What's the obsession with calling them 'radical Islamic terrorists'
It's to make a point that these people aren't just out there randomly attacking people. They have an ideology that is based on a radical take on the teachings of Islam. They're not just fighting against America, they're fighting against a way of life that they view as abominable to Allah, and they want to apply to tenets of Sharia to all people Muslim and non-Muslim. You have to identify the enemy and their motives before you can stop them.
No. Walkers description makes it clear in his mind the terrorists views are not radical. When he says that there are a handful of moderate Muslims are supposed to terrorist groups like Isis, he makes it clear that, in his mind, the terrorists' views represent mainstream Islam.
