growstuff
I don't think it's much to do with being Shia. As far as I know, Iraq is mainly Shia, but Iran and Iraq hate each other. Gaza certainly isn't Shia. The enemy for Iran is Israel, so Iran supports any conflict against Israel.
Iraq isn’t mainly Shi’ite, it is mainly Sunni with a Shi’ite population in the south, and Iran backed the Shi’ite in the South to defeat Saddam back when the west wanted Saddam out in the early 2000s because back in the 1980s there was the Iran/Iraq war which went on for many years. Oddly enough, or maybe not, the US backed Saddam to defeat Iran back then.
Seems the US will back any horse to defeat Iran.
Iran hasn’t historically had any reason to hate Israel but after 1979 saw it as a US pawn in the ME and after Israel entered into a conflict with Lebanon in the 1980s and
again in 2006 the Shi’ite population in southern Lebanon sought an association with Iran. And when Hamas was elected in Gaza, though they are not Shi’ite, again help from Iran was forthcoming. This was not the case with the PLO, nor is it the case with representation of Palestinians in the West Bank.
Iran hates Israel as an extension of the US, and basically has several massive axes to grind with he US going back to the days of the Shah who was a US puppet leader of Iran who terrorised the Iranian population every bit as much as the Ayatollahs who came after him. Back then there was one moderate and much loved Prime Minister who could have been the salvation of Iran, Mossadegh, who was overthrown by the CIA and British intelligence, in operation Ajax.
This then gave the Shah complete rule.
In 1979 the people had had enough and rose up against the Shah giving the Ayatollah a chance to take over. The rest is history.
It might surprise many to know that the majority of ordinary Iranians are not hardliners and the most pro European and pro US population in the ME, barring Israel.
Anyway that is a bit of background info if anyone finds it useful.