An optimistic analysis of how Iraqi politics have changed and what is likely after Daesh (ISIS) is defeated via WoTR:http://warontherocks.com/2015/02/ira.../?singlepage=1

Sunnis will be economically, geographically, and politically disempowered for a generation.

In short, the Kurds find themselves stuck with Iraq...
The Shia no easy quote! There is this difficulty though, as we know rumour can replace reality and we have seen similar legends in Afghanistan:
...it is commonly believed in southern Iraq that the United States not only refused to help Iraq against ISIL, but is in fact ISIL’s patron and sponsor. This belief is largely a product of conspiracy and paranoia, but does have a strong element of believability at its core from an Iraqi Shi’a perspective. When pressed on this belief, pushing aside rumors of direct aid by the United States, southern Shi’a ask how can the United States permit its allies — Saudi Arabia, Qatar, and Turkey are usually named — to provide aid and comfort to ISIL as they do? Their explanation is that these states are the middle-men, or proxies, used by the United States to empower ISIL for its own purposes.