Without evil there can be no good, so it must be good to be evil sometime.
Where I believe we may differ is that it is my opinion, that in order to preserve peace we must always be prepared for war. We must maintain the strongest military on the planet (they must train for war, not dig ditches in Lousiana), and sadly must keep terrible, terrible weapons at our disposal. But as the eagle emblem shows, we must have the arrow in one talon, and an olive branch in the other.
Amen, and well said. I would add that one must be prepared not just to wage war, but to wage it in such a way that the enemy is met with overwhelming force. If a potential enemy is assured of their destruction when diplomacy fails, they are far more likely to acquiesce. Of course, if self-preservation is a low priority (as it is with Iraqi insurgents and other terrorist types), then death becomes less of a deterrent. 
