Unfortunately for Iran when war will come, as I highly doubt it will be in the years to come they will find out they are alone, alone with no allies and nobody wanting to risk anything for them.
you are correct. actually about 40 years ago the war did come to Iran and they did have no allies, it was the early year after the Iranian revolution and they didn't even have any military either. all their equipment was also western made and they couldn't even fix an engine if it broke down and those countries had abandoned Iran. suddenly Iraq thought it could take advantage of the situation and take half of Iran.
yet Iranians fought the invaders who were backed by super powers such as US and other European countries that were supplying them all kinds of weapons including chemical bombs which were used on civilians. they defended their land for 8 years with 2 last years of it spent in direct conflict with US forces.
half a million people died in that war and yet Iranians didn't even give up an inch of their home to these invaders.
the new war will be different because now Iran has a strong military capable of mobilizing at least 2.5 million with an addition of 35 million fit to fight. it is technologically advanced enough to go toe to toe with supper powers.
i said this to tell you that war is a complicated thing. a losing Iran may not receive any help but a winning Iran that wasn't the starter of the war and is just defending and successfully at that will receive support from those two big allies. but those allies aren't the only allies Iran has. they have strong ties with half of middle east.