There's nothing more dangerous than a group that perceives themselves as the ultimate victim, and therefore feels anything they do is justified either as payback, or as doing whatever is necessary to protect themselves.

Neocons use this justification for their actions abroad, progressives do it domestically.

“Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive. It would be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience.”

― C. S. Lewis