It goes back to the days when we were defending ourselves against the internal aggression of the Native American population, who we incidentally wiped out in the process. In the post World War II period, we've frequently had to carry out defense against internal aggression, that is against Salvadorans in El Salvador, Greeks in Greece, against Filipinos in the Philippines, against South Vietnamese in South Vietnam, and many other places. And the concept of internal aggression has been repeatedly invoked in this connection, and quite appropriately. It's an interesting concept, it's one that George Orwell would certainly have admired, and it's elaborated in many ways in the internal documentary record.