I will explain my position starting from the broader picture and then going further into specifics.

1. Starting a war of aggression is considered by many to be the prime war crime as it that enables every subsequent war crime.
2. Wars of aggression contravene the UN Charter, and therefore outside of extremely extenuating circumstances, the defending party is by default in the right.
3. The United States is the global hegemon, while Iran is a mid-sized state fighting against imperial domination. Iran is therefore de-facto fighting for the rights of all countries against imperial domination.
4. The US started this war during negotiations, which were in fact just a ruse to cover for the impending war. They began the war by assassination Iran's civilian leadership, which is itself a war crime, and blowing up an elementary school, killing 180 little girls (also a war crime, if I actually have to explain this to you).
5. US/Israeli leadership are nazi pedophiles.
6. Israel, enabled by the United States, is presently committing Genocide against the captive Palestinian population. Genocide is the greatest crime against humanity in international law, making all other crimes pale in comparison, and any country fighting against a genocidal country is by default the side to support.

Therefore, Iran is by a wide margin the most just belligerent in this war, and your equivocating them with the United States and Israel is basically like equivocating the WW2 allies (who were no angels, remember - the US had segregation, the British starved millions of Indians) with Nazi Germany.

Your snide reddit-style comment - "le heckin authoritarians are bonkin' each other!" - is in extremely bad taste given the crimes against humanity that are being committed daily, and is indicative of a chauvinist worldview that speaks very poorly to your character.