"We need to walk a very high, tenuous tightrope between bringing a definitive end (i.e., total eradication) to forces of actual -- not conceptual -- evil in this world, and preserving our own fundamental freedoms. This crossing is where we will most need God's help."
"Eradication" and "God" (in the true Christian spirit) are 2 words which oppose each other.
Christianity does not advocate the destruction of evil by violent methods. The fight against evil is intended to be personal. It is best fought by turning away from evil and doing good, but never doing evil. A wrong cannot be used to right a previous wrong.
Things like wars pose a pretty big theological problem. There is obviously a level that can be reached where one can help defend against a truly evil enemy (as was the case in World War 2) in a defensive way. However, even in the most threatening of wars, the virtue of loving one's enemy is applicable.
I think that if people are in danger of being killed, it is okay to step in and stop the enemy from bringing down the blows, but it should be done for the sake of others you love. And if you are a truly good person, you will condemn yourself for your actions, even if you realize there would not have been an alternative without loss of life. It must not be done out of hatred. God judges justly, and I'm sure He will understand if you felt you had no other alternative (we're really talking extreme situations here) AND if you are sorry for doing it.
We must also be careful not to let "pride", "dignity", and "honor" get in the way of our judgement and hurt innocent people around us. "Not going down without a fight" just for the sake of "not going down without a fight" is not a good enough reason.