Thanks to this "tend to assist one another", Iran's borders extend all the way Lebanon, Iraq, and beyond. Iran literally invaded Iraqi oilfields and guess what the Shia Iraqi's in govt do? Instead of threatening Iran to vacate, they urged the Iraqi govt to negotiate! So Iraq is filled with Iranian puppets to ensure the country never becomes independent and is an extension.
Remember the Iraqis protesting not too long ago? Puppets in the Iraqi govt and so-called anti-Iran Sadr party helped crushed those protests, mostly Shia brethren.