"I don't consider proposals to round people up en masse to have anything to do with "backbone.""
If the people in question to be rounded up follow a manual that teaches hate and intolerance. And the individual in question refuses to acknowledge said teachings. Then I'd propose there is a lack of intelligence, or a lack of backbone, or some combination of the two in said individual.
How, exactly, would you determine this? How does one go around figuring out whether a certain person actually follows the tenets of the Koran to an extent that they're willing to commit acts of violence?