I have a little theory about how Christian theology was use as a tool in a recent war. Maybe I'm wrong, but here it goes:
George W Bush is known because he's a Christian nutjob, maybe in 2003 Iraq war he was deceived by some people who made him believe that he was fulfilling Christian prophecies about Babylon (Iraq) destruction, to make him feel less guilty for that nonsense war.
Of course that doesnt mean that the prophecy is the cause of war, but religious prophecies can be used to make people support some act.
The way I see it, the issue is not that political leaders may have eschatological religious beliefs but what those beliefs entail in some cases.
First off, there's a difference between passive messianism - the arrival of the saviour does not suppose any specific actions to be taken by the faithful; and active messianism - the idea that in order to bring about or hasten the messiah's advent, there are certain expectations believers need to conform to.
This said, not every form of active messianism is deviant or warmongering. Some religious Iranians supportive of the Islamic Revolution for instance believe that Imam Mahdi's (aj.) return can be accelerated if they increase their efforts in being good virtuous Moslems. A more political belief suggests that they should struggle in pursuit of the goals of the Islamic Revolution.
However, this must be done within a defined framework of what is permissible and what isn't. In Iran's case, religious principles as understood by officials of the Islamic Republic, definitely prohibit waging offensive war of conquest. So there's no risk that the Iranian Leadership out of messianist motivations would order military aggression like the US regime's invasion of Iraq in 2003.
Where active messianism becomes dangerous is when it based on incorrect interpretations of religion, namely when:
1) Its adherents consider offensive war to be justifiable.
2) In an even more twisted and namely antinomianist way, consider that it's permissible to directly contribute to the conditions prevailing during the final days as described in religious scriptures - knowing that said conditions are marked by a profusion of sins, by chaos and wars. In other terms, instigate wars and promote sinful behaviour among the people because supposedly this would create the conditions for the messiah's manifestation and thus shorten the remaining time.
In this context, I'd suggest researching the topic of false Jewish prophets such as Sabbatai Zevi (Tsvi) and Jacob Frank (who proclaimed to be a reincarnation of the former), and the political influence they had.
.
