This was discussed here when U.S. invaded Iraq.
Some thought it might be a good idea to form three nations, one to each ethnic group, as others claimed that such carving would only hasten the civil war. Also Iraqi themselves might have a thing or two to say about slashing their nation.

Also it was concluded back then that should Kurds gain more independence, they would start assaulting Iran and Turkey in order to gain land from them, which in turn would bring new Iraq and U.S. against Iran and Turkey.

Kurds want those lands, they want to form Kurdistan and will not stop in the autonomy of Iraqi Northern parts.

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En uneksi. I do not dream.