If this is the only reason, they must have a different Bible than the one I have. Mine has a lot of militaristic language.
Broadly put, there is little in the New Testament to suggest a bellicose bent to Christians, although Jesus warned his disciples to take at least a minimum of self defense, and Christian principles would suggest this be carried out to protect at least family and fellow believers, if not an arbitrary home land. The armies of Revelation are of heavenly origin, and the Old Testament read at face value is centered around a one-off earthly arrangement for a particular race (actually, set of races — Ishmael is quite busy fulfilling his role as trouble maker today).
My Bible teaches that GOD HIMSELF can get pretty violent when he is angry.
LLS