No, it doesn't. Fear might; anger might; mass hysteria might - but those emotional states are not confined to belief; if anything, they're belief-proof. All kinds of other institutions - the main one being the nation itself, but private schools and sports clubs and fraternal lodges might also qualify - provide a platform for mandated actions that would be inappropriate, or unlawful, or wrong in civil life. But even there, the ones who take part in atrocities are already so inclined; they just need permission to act out their baser drives. It's hard to persuade even the most patriotic soldier who is not already inclined to cruelty, to torture a POW or rape an enemy child. (unless, of course, he's been psychologically damaged beforehand... yes, armies do that, systematically and routinely.) It's just as hard to persuade even the most zealous Baptist, who is not inclined to violence, to shoot an abortionist or beat his disobedient child. People interpret their religious teaching, as well as their national loyalty, according to their own conscience; they each carry out the same teachings according to their own temperament.