Iranian Hegemony Is a Figment of America’s Imagination

I usually agree with most things I read in FP, but on this topic I have to respectfully disagree. Iran does have a hegemony over the entire Shia population in the region with almost all other Arab countries having dominantly Sunni populations. In layman's terms it is the defacto Shia nation state as Israel is to Jews and Saudi Arabia is to Sunnis.

Iran inserts itself into other sovereign nation states domestic woes, either directly through the Revolutionary Guards as in Iraq, or indirectly through its proxy Hezbollah as in Israel; and always under the auspices of protecting a Shia population. Think southern Iraq, western Syria, etc...If that's not hegemony I need to go back to school.