The U.S. should have remained vigilant in its efforts to help Iraq rebuild. It is necessary to step in at this point to restore order and help stabilize conflict in the region. Otherwise, years or war and thousands of lives lost were in vain. A developing nation with new leadership needs support.
The dogs of the US Army tried and failed in Iraq once, the mujahideen of Dawlatul Islam have conquered about 50% of Iraq now, there is no way the US or the Iraqis can take it back now. The khilafah has been established and no matter how much the world barks and creates lies against it it will remain and will expand inshallah.
I do think we need to send doctors and other helps over to assist the civilians of Iraq and try to help them, but we should not be sending military personnel over to try and attempt to control the situation. Clearly we cannot control the situation or force them to have a democracy if they aren't ready. Our best bet is to try and assist the civilians and stay out of it politically.
To say that the U.S. should step in to help the Iraqis begs the question, "Who are the Iraqis?". Iraq is a cobbled together state that consists of Kurds in the north, Sunni in the west, and Shiites in the south. I believe that the region should be allowed to divide into three autonomous states. Getting involved in Iraq again would be counter productive to our interests. Why should we support the Shiite regime, which is heavily influenced by Tehran? No, it's better to wash our hands of this disaster.
The U.S. should definitely stay out of the conflict in Iraq. By going to war there in the past, we spent a ridiculous amount of money, lost American lives, and achieved little progress. The Iraqi's need to handle this conflict on their own, and foreign intervention should not be an option.