Iraq was invaded on the pretext of WMD and harboring AQ and not in support of Kurds or Shias, if that had been the case, US would have done it way back in 1st Gulf War when it had routed the Iraqi Army and could have easily captured Baghdad, rather they left the Kurds and Shias to be more slaughtered, which can be seen in reports coming after 91 war.
So Iraq was not invaded to protect Kurds or Shias, plzz update you knowledge about the reasons for invasion of Iraq, it was WMD and AQ not what you have just told.
If US is so kind hearted then it should send its forces all over the world wherever regimes, democratically elected countries are involved in oppression and killing innocents. Why it has never sent its military in Africa to stop various genocides, where more people have been killed compared to what Kurds and Shias were killed.