Who do you think is responsible for our failure in Iraq?

I think its the Iraq Government's fault. I mean the saying goes "You can only lead the horse to the water, but you can't make it drink"

Well it appears not all Iraqis lack the stones to face ISIS. Footage from a recent Iraqi Air Force mission that morphed from a humanitarian supply drop to impromptu rescue.

Look at those door-gunners get some! I believe one is even wearing a 4ID patch on his helmet...

Lets remove the word "our" from your question. US and allied forces captured a ruthless dictator, secured strategic land, quelled a raging dispute between religious sects, and left a relatively secure country after our withdrawal. In short the forces involved accomplished the complex missions assigned to them with compassion and firm resolve.
At home any failure lies in the politicians taking advantage of a hot subject to create divide within our population, draining support from the mission to create a situation that may shift enough votes for a change in the political landscape.
In Iraq it is squarely the fault of an elected government failing to push forward after 10 years of political discourse and debate being settled by arms. Nominating weak leaders in positions that could matter to ensure no matter who was elected no viewpoint can win out.

Did you forget Obama's refusal to establish a status of forces agreement? Yes, firing the Iraqi military was a HUGE bonehead mistake, but leaving was even more so. We still have troops in European countries and Japan 70 years after the end of WWII. Leaving Iraq gave the Global War on Terror high ground back to the enemy. It will take more now to get it back, but it's not worth it if we're not going to stay. We need a Middle East Marshall Plan. We need to retain bases and authority to operate in order to project power and influence.

Obama. Obam, Obama, Obama is responsible for the retreat and early pull-out of Iraq. Obama gleefully withdrew and gave that jerk-face, smug smirk of his, gloating that Iraq was "stable" and well prepared to take care of itself. Obama is a cancer leading us to ruin in every capacity.

You battle religious fanaticism through literacy and education, and it takes decades to move a country like Iraq into the 21st century. When we focus on military victory we lose sight of the harder long term victory in which everyone truly wins.

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My personal take is that we didn't stay long enough to ensure security for a whole generation of Iraqi children to become literate and grow up. We are now witnessing the result.

I was never in Iraq, my career took me to Egypt instead, however I have studied the situation extensively during my Graduate studies and written various papers on it. Further, I have had long discussions with my own peers who were on our battalions two tours there:

There are several reasons why Iraq failed after we left, some were senior leadership decisions, others were beyond the control of any American or coalition partner;

1) Decision to disband Iraqi Army, (De-Ba'athification) -- This essentially exiled the experienced Iraqi leadership from the new government in 2003, when we needed them most. (Bremer mainly, but Bush also contributed to this) This would force them to turn to the Fedayeen and later AQI

2) Abject failure to understand the inter-and intra-ethnic dynamics of Iraq, Intel should have been watching this but they were too concerned drinking the "All Iraqis want Democracy" Kool-Aid.

3) Attempts by senior commanders to use traditional maneuver tactics against an insurgency in utter defiance of everything we (should have) learned from Vietnam, the French experiences in Indochina and Algeria and the British experiences in Sudan, Oman, Palestine, Malaysia and more

4) Insisting on a democratic government in a country that has no history of democracy. Democracy historically evolves from a more authoritarian level of government after economic development is established. Even the American colonies had a developed export based economy and a monarchial government before the American Revolution. This doesn't necessarily mean a dictatorship nor communism, South Korea began with a right-wing military junta, no it is a vibrant world class economy governed by an elected federal system.

5) Foolish insistence that Iraq remain a united country composed of three disparate ethnic groups, that hate each other, just because when the French and British drew the current borders of the Middle East in 1918 with the Sykes-Picot Agreement that was how they wanted it. It would be better to split into three states, one for each of the Kurds, Shi'ites and Sunnis and maintain separate relations with all three.

6) This is actually the biggest one; Rampant corruption and laziness at all levels of the Iraqi government, military and civilian sectors. Enough said.

Condoleezza Rice. Former Sec State. From Jan 20, 2001 until Jan 26, 2005 she was the National Security Advisor who served as the chief advisor to the President of the United States on national security issues, which is what Iraq was. This is the same Rice who wrote the following: “The president must remember that the military is a special instrument. It is lethal, and it is meant to be. It is not a civilian police force. It is not a political referee. And it is most certainly not designed to build a civilian society.” - Condoleezza Rice, then a Senior Fellow at the Hoover Institution writing for Foreign Affairs Magazine, January-February 2000 issue.

She was beating up then President Clinton over Somalia so she knew full well the futility of what she proposed in Iraq. We went in and the military did it's assigned task and then the US Dept of State sent in Bremer as the Caliphate. There was no planning or consideration of Iraqi wants or desires for an end state. I was in Baghdad in 2006 as an advisor to the General Counsel of the Iraqi Armed Forces and nobody ever asked the Iraqis a damn thing. GEN Martin Dempsey just pushed the State agenda --you will become a democracy and worked on standing up 18 Brigades. I'd blame Dempsey for insisting on US Doctrine when the Iraqis understood British doctrine. I'd blame war profiteers who just sent crap that seemed to somehow satisfy our quality requirements. The entire operation was just too big and too unfocused. There is plenty of blame to go around and the only person who ever accepted any blame was poor old Jay Garner, the head of the briefly alive ORHA the original agency commissioned to oversee the reconstruction. There have been two great reconstruction efforts in recent times. The first was after the US Civil War and the other was the Marshall Plan. Iraq was much closer to being like the former.

I say our government. We did just what we did in Vietnam and suffering the same result. What I saw us do is provide so much support and money and equipment and supplies that we rendered them dependent upon our resources and troops. We tried teaching them, they didn't learn. We paid for all the damages done, all the goats that got blown up, etc... Once we ceased support and started removing ourselves its like a bird falling out of the nest but can't fly because it almost relied completely on its support system to provide. Once it was gone, they didn't know what to do. Kind of like the S Vietnamese during the Vietnamization stage.
I see the same thing happening in Afghanistan: We are training/trained them but based on my experience with them, they are completely unable to support themselves, incompetent and untrustworthy leadership, and once again have almost completely relied on US support to continue their mission. I do recall reading the news about the Afghani President wanting us to leave the country but wants us to continue to provide financial support. If you haven't figured it out in the 10 or so years we've been there, you aren't going to figure it out now.

The current administra is completely and totally responisble for Iraq falling into the hands of the enemy. I lost brothers and left flesh in that desert and for the administration to completely pull out and turn a blind eye to the invasion clearly for political reasons and campaign promises is unacceptable.