Iran has been funding a lot of the "attack Israel" groups in the area. When your income depends on hating Israel it is hard to see a more moderate view. In turn this gives the extremists in Israel a better line of why elect them over someone more moderate. (Lets me clear I'm not trying to clear Israel of their crimes here, only suggesting that Iran bares some blame for those crimes).

The above, but applied to other countries and not as extreem. Iran is funding many anti-democracy groups in the region.

Iran has a lot of smart, well educated people - who can't get enough water to drink. If Iran had a better government those people could develop things of use to improve the world, but instead many are stuck as poor despite having the ability to not be.

Changing Iran would not solve all the problems, but it would ease a large share and maybe leave room for a better world. The only question is how to do this - world history doesn't have a good record for changing evil governments.