Imagine that you are the Prime Minister of Iraq. You are the head of a political system that was imposed by the invading Americans. A substantial, but diminishing, part of your country is controlled by IS. The Kurds are your nominal allies in the battle against IS, but their ultimate objective is independence. The Turks want a slice of your country. Iranian influence is very strong, but is opposed by everyone else. A political solution satisfactory to both Shias and Sunnis is nowhere in sight, but is essential if your country is ever to operate as a functional whole.
Now, add to the mix a new American President who was bitterly critical of the invasion after the fact and continues to say that the US should take Iraq’s oil. In all likelihood, the best you can hope for is a victory over IS before he takes office, and indifference thereafter. It is, alas, much more likely that the chaos in your country will simply morph into different forms after the demise of IS, and you will no longer be able to rely on America for help.
Good luck: you’re going to need it.