Iran has rich and successful neighbors in the gulf ,
But instead of being happy and keeping good relations and flourishing business with them , the Mullahs think it better to make their life as miserable as possible and encourage all sort of groups to fire missiles on them.
Actually it's the other way around. Instead of welcoming Iran's offer for a common defence pact to ensure the security of the Persian Gulf jointly, a proposal that's been on the table for decades, these regimes have preferred to rely on extra-regional, imperial powers with a sinister track record in the neighborhood, mainly the US, France and UK, to whom they are subservient and which have no business whatsoever dispatching military forces to the area.
PGCC regimes prefer to play second fiddle to NATO and the zionist entity in the non-stop destabilization and nation-wrecking policies pursued across the region by these powers: from financing and supporting terrorists who plunged Syria into war, to providing bases to the US from where Washington waged both its wars on Iraq (1990-1991 as well as the illegal 2003 invasion based on bogus, fabricated pretexts of non-existing WMD), to partaking in the organized obliteration of Libya, to funding Saddam's military aggression against Iran (1980-1988) and associating themselves with zio-American plans for "regime change" in Tehran (backing terrorist and separatist grouplets, sponsoring anti-Iran media including satellite broadcasters, bankrolling the exiled opposition), and now invading and bombing Yemen, which has a right to defend itself against this aggression.
Rather than lowering themselves to such depths and spreading this much destruction, they could have joined hands with Iran and the Resistance, which would have allowed them to recover their sovereignty and experience what it is like to enjoy actual independence and self-determination. But they preferred servitude to imperial masters, which will likely end up suppressing them too as soon as their expiry date is reached, for this is how imperialists have always treated their vassals and patsies. Go figure.