Iran-Iraq war?

Question

Can someone tell me why the countries listed below picked a side to support?

"Iraq was financially backed by Egypt, the Arab countries of the Persian Gulf, the Soviet Union and the Warsaw Pact states, the United States (beginning in 1983), France, the United Kingdom, Germany, Brazil, and the People's Republic of China (which also sold weapons to Iran). All of these countries provided intelligence, agents for chemical weapons as well as other forms of military assistance to Saddam Hussein. Iran's principal allies during the war were Syria, Libya, and North Korea." (Wikipedia)

Answer 1

Money. Most of those supporting countries sold weapons to the governments, or got cheaper oil. Except for the US. Their point there was that Saddam was considered the lesser of two evils. Also, Libya and Syria were satilite states of Iran.

Answer 2

Iran supporters all also happen to be anti-US and allies in terrorism with Iran.
Persia (Iran) is an age old enemy of the Russia (Soviet Union) and they had a common border at the time. This provides a lot of reason for the Russians to support the country fighting them. The Warsaw Pact supported whoever the Soviet Politburo told them to.
France has a pretty historical alliance with Iraq and was key to it's formation.
It should also be noted that NATO and Warsaw Pact countries were both vying for allies and influence in the Middle East and Iran wasn't really looking too good for that.
The United States is probably the easiest one, since Iran had so recently taken our citizens hostage. Prior to the "Islamic Revolution," Iran had been our close ally and the deposed Shah was probably still living in the US then.
Germany falls under NATO as does Great Britain, but there may have been more reasons for both of them other than the threat Iran posed in it's radicalism. Great Britain was also a key in Iraq's formation.
China and Brazil were probably doing it ONLY for the financial considerations of weapons sales and oil, but they too could have been looking at the radicalism of Iran. Brazil was still just getting off the ground with weapons, but China also has a muslim minority.
The Arab countries of the Persian Gulf are primarily Sunni (as was the Baathist party and Saddam) fighting the Shi'a radicals which was/is a threat to them.

Hope that helps. International politics ("diplomacy") is such a tangled web of enemies of enemies that sometimes enemies must take up the same side.

Answer 3

As far as the U.S. goes, the ultra-religious Iranian leaders were a bigger enemy at the time. Supporting Sadam, who was more open to the west, seemed to make sense.