no, atheists cant win war with believers because atheists afraid to die in war
What you fail to realize is that even if that were true: it doesn't matter.
It USED to be true that in order to win a war you needed people willing to die in war. That hasn't been true in a long time, however. Being willing to die in war is meaningless when your enemy has high-altitude stealth bombers that can flatten entire mountains. Modern wars are won by 1) having superior technology, 2) having an unbroken chain of supply, 3) have sea/air superiority. Whether or not individual soldiers are willing to die or not is almost entirely irrelevant.
you should try that with russia
if you fight with you equal power atheist will run away