Hold on a Second...

I was watching a show on the AntiChrist yesterday, and a thought came to me. According to the breakdown, at the time of the Rapture, all of the Christians (however that's defined) are taken away to be in heaven with Christ, and then there are seven years of tribulations, and then a huge battle between good and evil ... So if you consider the battle of/at Armageddon to be an actual fight between Earthly armies, doesn't that mean that everyone fighting on the side of God in the final battle is a non-Christian at the time of the Rapture?