Sea Breeze you made a number of good points regarding the position on war, but at least the JWs in Germany and Japan were not in the German and Japan armies. The JWs in those countries were not the enemies of the Allied military forces. Furthermore if you believe the Bible is true, then you believe that people faithful to Jesus and God will receive a resurrection to eternal life.
Regarding Cornelius, we don't know if he remained in active duty in the army after becoming a Christian. Regarding what the Bible says in Luke 22:36 keep in mind what the Bible says Jesus did when an apostle (Peter, a zealot) of Jesus used his sword to cut off the ear of the slave/servant of the high priest. Some people say Jesus used the words said at Luke 22:36 as a teaching example (such as to Peter) to later illustrate (at the time of the ear but cut off and then restored) that one should not use the sword. Keep also in the mind the words attributed to Jesus about he who fights by the sword shall die by the sword. The verses you used could also be used to argue that the Bible is contradictory in its message and thus not the word of God.
The Bible, such as in the book of Revelation, teaches that it is better for Christians to die as martyrs that to kill others (see the passages about the time of the antichrist and the beasts, and of those slain but who later go to heaven to rule with Christ).
Other than the JWs and the SDA (but the SDA might no be fully consistent in this matter0, I don't know of any Christian religion/denomination/sect with more than about 100,000 members worldwide that forbids its members to serve in armed combat. However Buddhism and Jainism are religions which are firmly against the taking of human life, even if it means that the their own members will be killed and tortured as a result in their present human life.
It takes courage in totalitarian countries (such as North Korea) to refuse military service, knowing you likely will be tortured and possibly executed as a result.