Saying it was wrong to destroy the Saddam regime because it turned over Iraq to Iran is like arguing that destroying the Hitler regime was wrong because it turned large chunks of Europe over to the USSR. One job done does not mean there are no more jobs to do. So Cold War followed hot World War II.
My view was that Iran long had influence in Iraq (that's one reason Saddam invaded Iran in 1980) and that our influence after the war would be key in fighting against that influence. But we left in 2011 and ISIL rose up. And Iran increased their influence in Iraq by sponsoring militias to fight ISIL after many Iraqi security forces collapsed in mid-2014.
After ISIL was defeated in Iraq War 2.0 we decided to stay. And our influence worries Iran a great deal:
Reports have been circulating about Iran’s reduced influence and popularity in Iraq. According to a study that Alustakilla research group conducted and The Washington Post published Nov. 16 that involved 2,500 to 3,500 national interviews, Iraqi Shiites favoring Iran dropped from 88% in 2015 to 47% in the fall of 2018. During that same period, the percentage of Shiites who do not favor Iran rose from 6% to 51%.
The percentage of Shiites who believe Iran is a reliable partner of Iraq plunged from 76% to 43% during the same period. Those who believe Iran is not a reliable partner increased from 24% to 55%. More Iraqi Shiites now see Iran as a real threat to Iraq’s sovereignty, with a rise from 25% in 2016 to 58% in 2018.
Iran is desperate to maintain their friendly Popular Mobilization militia units that are a proto-Hezbollah answering to Tehran. We need to keep up our pressure and support for the Iraqi government to bring those militias under central government authority and to disband those that resist.
Fighting for Iraq is not futile. Iran has problems persuading Iraqis if the Iraqis have an alternative. We need to be that alternative.
Strategypage's tour of Iraq discusses ISIL's lingering presence, divisions among the Iraqi Kurds, continued problems of Iraqi leadership in Mosul, and Iran's efforts to retain influence in Iraq. And more. There is much to do still.
We forget we won the Iraq War all too easily.
*I originally wrote "Iraqis"--which is what we did. I hope the context made my slip clear!