Romans chapter 2:29 says that real circumcision is a matter of the heart. That means that Christianity is a matter of the heart. If you have peace in your heart, then it is your responsibility not to be a hypocrite and be true to what you believe If you serve the public as a Police Officer or are charged with preserving the peace and protecting the public in any capacity, your duty is an honorable one and I believe it is sanctioned by God, which, of course, includes killing FOR A GOOD and JUST REASON. If you believe that the reason for a particular war is a good enough reason for you to kill another human being, and you will be able to stand before God with a clear conscience, then, you might be on the level as a Peace Officer, MIGHT BE (depends on whether YOU can really have a clear conscience about what you've done).