All totalitarian states claim their ideology is world-applicable and gives them the right to subdue others. Iran has tried to export its ideology to other Moslem countries, but with the exception of the Hezbollah militia in Lebanon, whose loyalty is bought with a gravy train of guns, it has failed. It has tried to weld together Moslem fundamentalists in other countries into a worldwide fundamentalist movement, but as Stalin found with Tito and Mao, totalitarian ideologies make weak glue. It does not even get along with the Taliban in Afghanistan, which should be its ideological soul mate. The third pillar is war.
War follows from the demand to export ideology.
It provides the excuse to regiment society to the degree totalitarianism requires. It enables the regime to equate loyalty to the nation with obedience to the regime. It justifies the regime's inevitable failure to deliver on its promised domestic agenda. Iran did not start the Iran-Iraq war, but it, together with Saddam Hussein, endlessly prolonged it past several opportunities to disengage. The fourth pillar is terror.