Democracy and Theocracy

All democracies are theocracies, although they'll fail to admit it. Let's take, as an example, one state from each supposedly adverse national system and then compare them: Iran and USA.
Iran has many political parties and all those political parties are Islamic and it has elections. The USA has only two political parties that have any clout at a national level and it has elections too, and any candidates for national election are expected to be excellent fund raisers, or else they will not be nominated by their respective parties; presidential elections in US cost over a billion.
Power in both countries resides in the hands of plutocratic oligopolies as it does in all countries. The big difference between Iran and USA is that one country, Iran, requires a specific religious affiliation (to Islam in its case and specifically Islam's Shia version) and the other country, USA, in its Constitution, specifically prohibits a religious affiliation or lack of affiliation as requirement for public office. Big difference one would say. But, not so. What is required for holding public office in the USA is a swearing by an allegiance to and defence of, its USA's Constitution. In Iran, a same swearing of an allegiance to and a defence of, is required; but in it's case it's to Ar Qur'an.
Differences in interpretations of both documents, Constitution and Koran, are decided by black- robed panels, judges and clerics, and judgments can be appealed to higher levels of black-robed. So where is the difference? After all, in Iran, you don't have to spend your billion to be elected! The difference is this: The Constitution can be amended and The Koran can't. USA can change.