Of course they demand that::
Two Iraqi Shi‘ite groups backed by Iran are demanding all U.S. forces leave Iraq, opposing plans by Baghdad and Washington to retain some in training and advisory roles.
But Iraqi Prime Minister Haider al-Abadi told reporters U.S. forces were needed “to completely finish the job” of destroying Islamic State in Iraq and Syria.
You can hardly see Rouhani's lips move when those group leaders say that!
With ISIL a terror threat rather than an occupying power, Iran is the main threat to Iraq.
Iran was one big reason I wanted 25,000 American troops (from multiple services) to remain in Iraq after 2011 (including three combat brigades to deter Iran and special forces to hunt jihadis, along with air power). I wanted a solid contingent to resist Iranian efforts to subvert the government and cripple rule of law.
The rise of ISIL was enabled by the American exit which allowed corruption to cripple the Iraqi army as loyalty rather than skill were valued. Why was loyalty needed? Because the Iranian threat to rule of law and their influence meant that Iraqi leaders felt they needed loyal commanders for internal fights outside of rule of law.
And the rise of ISIL provided a reason for Iran to expand their influence in Iran to fight ISIL. Many of the militias are friendly to Iran, which Iran hopes to turn into their own Hezbollah in Iraq.
So the task of rolling back Iranian influence that undermines Iraqi democracy is harder now post-ISIL than it was post-al Qaeda and post-Sadrist (pro-Iranian) death squads in 2009.
On the bright side, most Kurds, Sunni Arabs, and Shia Arabs don't want Iran to dominate Iraq.
Let's get to work. I hope the smaller contingent we'll leave now is sufficient. At least Iran is worried enough about what we will leave to have their hand puppets bitterly complain.