Economic prognosticator Nouriel Roubini writes at the Project Syndicate website that he expects the regime in Iran to fall with the next year. Here he summarizes its problems.
Today, Iranians face skyrocketing inflation, collapsing real incomes, mass poverty, and even hunger not because of US and Western sanctions but because of their rulers’ nonsensical policies. A country that could have been richer than any Gulf oil state is near bankruptcy, owing to the regime’s corruption, incompetence, and strategic recklessness. (emphasis added)
In addition to being a curse to its own people, the Islamic Republic has financed terrorist groups in the Middle East for decades and has caused state failure or semi-failure across the region: in Yemen, Lebanon, Syria, Gaza/Palestine, Iraq.
When nations put a cause ahead of their national interest, they don't do well in the longer run. Iran is certainly the example of this currently in our news. When Russia wore its Soviet Union hat, it too was the world headquarters of a cause - Communism - and it too found that didn't work out well - the "hat" is no more.
Even the US has flirted at times with pushing the cause of democracy and representative government. Its experiments with "nation building" have most often failed.
I conclude that just as separation of church and state is a good governing principle, more generally the separation of state and any cause (religious or otherwise) is likewise preferred. Cause-driven governments suboptimize routine business, at the expense of national life, in order to prioritize the cause, normally beyond their borders. The nation suffers from this neglect.