Asked this week to respond to criticism of his judgement on Iraq, like his Senate vote to authorize the use of force in 2002, and his much-derided later proposal to divide the country in three along sectarian lines, Joe Biden laughed and assured Asma Khalid of NPR that “the vast majority of the foreign policy community thinks it’s been very good.”

It was not clear if the former vice president had any specific foreign policy experts in mind, but the interview was recorded just after the death of Leslie Gelb, former president of the Council on Foreign Relations who advised Biden on Iraq. As Biden recalled in a statement on Sunday, three years earlier, Gelb had co-authored his 2006 plan to pave the way for the United States to withdraw its troops from Iraq by segregating the country’s three major ethno-religious groups — Arab Shias, Arab Sunnis, and Kurds — into self-governing regions.

“Whether it was overseeing the Pentagon Papers in his early days, pushing the Council on Foreign Relations to open itself to new members and new ideas, or finding himself next to me on a plane in 2006 and spending the entire flight hammering out a new proposal for Iraq, Les was never afraid to stake out a position outside the mainstream because he thought it was the right thing to do,” Biden wrote. “Our Biden-Gelb proposal to federalize Iraq wasn’t popular in Washington at the time, but I still remember that plane ride as one of the most enjoyable I’ve ever taken — because I got to spend it trading ideas with one of the best foreign policy minds our country has ever known.”

Biden’s description of how enjoyable it was for him to work with Gelb on a plan to remake multiethnic and multiconfessional Iraq into three states, partitioned along ethnic and religious lines — which prompted dismay from Iraqis and condemnation from experts on the region — is a reminder of just how removed from reality Washington’s foreign policy community was and still is when it comes to dealing with the unintended consequences of American military interventions.

Gelb himself seemed more aware of the dangers of being part of what Ben Rhodes, a former Obama aide, called “the Blob,” the permanent, bipartisan American foreign policy establishment whose members move in and out of government, between stints in academia and the opinion pages of the nation’s leading newspapers.

In an analysis of the failings of the American media in the run-up to the war in Iraq, written in 2009, Gelb was critical of the role think tanks like his had played in pushing for it. “My initial support for the war was symptomatic of unfortunate tendencies within the foreign policy community,” Gelb wrote, “namely the disposition and incentives to support wars to retain political and professional credibility.”

In his NPR interview this week, Biden was less willing to admit his support for the war a misstep. He defended his vote in favor of the war by claiming that, before he cast it, “I got a commitment from President Bush — he was not going to go to war in Iraq.”

“He looked me in the eye in the Oval Office,” Biden recalled. “He said he needed the vote to be able to get inspectors in, into Iraq, to determine whether or not Saddam Hussein was engaged in dealing with a nuclear program. He got them in and before you know, we had ‘shock and awe.’ Immediately, the moment it started, I came out against the war at that moment.”

While Biden was quick to criticize the conduct of the war, and George W. Bush’s decision to attack without United Nations support, it is simply not true that the then-senator from Delaware “came out against the war” after the first strikes on Baghdad on March 20, 2003.

Four months after the American attack, Biden gave a staunch defense of the invasion to a roomful of foreign policy experts at the Brookings Institution in Washington. “Nine months ago, I voted with my colleagues to give the President of the United States of America the authority to use force, and I would vote that way again today,” Biden said on July 31, 2003. “It was a right vote then, and it’d be a correct vote today.”

Citing Saddam’s supposed defiance of U.N. security resolutions to end his pursuit of nuclear, chemical, and biological weapons, Biden called the war necessary. “Contrary to what some in my party might think, Iraq was a problem that had to be dealt with sooner rather than later,” Biden said. “So I commend the president. He was right to enforce the solemn commitments made by Saddam. If they were not enforced, what good would they be and what value those institutions?”

As Biden acknowledged this week, the plan to divide Iraq along ethnic lines he cooked up with Gelb was criticized at the time as more likely to incite than tamp down sectarian violence and ethnic cleansing, as it had early in the war in Bosnia and following the partitioning of Ireland, India, and Palestine in the last century. In each of those prior cases, partition, which looked good on paper and was accepted enthusiastically by extreme nationalist/segregationist leaders in each place, had the same result in practice: It encouraged violent sectarian cleansing and the destruction of the multiethnic societies that had existed in those territories for centuries.

After they published the idea on the New York Times op-ed page, in May 2006, “It got a lot of attention — almost all negative,” Gelb told Evan Osnos of the New Yorker in 2014.

But when he ran for president in the 2007 Democratic primary, Biden found it useful to pivot from questions about his vote in favor of the war to discussing his plan to end it. At a debate in Iowa in September 2007, Biden said that, as president, he would push Iraqis to embrace his plan for a federal system modeled on the division of formerly multiethnic Bosnia into regions for each of its three major ethnic groups: Bosnian Muslims, Croats, and Serbs.

The result, Biden said, could end civil war in Iraq and bring about the relative peace enjoyed in Bosnia after power in the country was divided along ethnic lines in the Dayton agreement.

Speaking in New Hampshire that November, Biden described it as “the Biden exit strategy.” “It does something very basic,” Biden explained to voters. “It decentralizes power, gives the Iraqis local control over local police, jobs, education, and services.”

That December, Biden sold his plan to caucus voters in Iowa as “the only a concrete specific initiative, how to end this war, to get your son home and my son, who is about to go.”

Rejecting criticism that his plan was a form of partition, Biden pitched it as a modified form of American democracy. The three Iraqi groups would simply be offered the opportunity “to vote themselves to be a state or not a state — like the state of Iowa versus the state of Minnesota versus the state of Delaware.” Of course, with the possible exception of Utah, American states are not organized as homelands for any one religious or ethnic group.

As he campaigned in Iowa in late 2007, Biden passed a modified version of his plan as a nonbinding senate resolution co-sponsored by Sen. Sam Brownback, a Kansas Republican who was also running for president at the time. The two senators appeared together to promote it. In his own campaign video, Brownback described the plan as “a three-state solution” based on “a soft partition” along ethnic and religious lines.

Reidar Visser, a research fellow at the Norwegian Institute of International Affairs, was dumbfounded at the time to see Brownback display an Ottoman-era map and claim, inaccurately, that the three provinces in what is now Iraq, where ethnic and religious groups had lived together, were each dominated by one group. “This is in the State of Mosul, the Kurdish north,” Brownback told the Senate, of a region that was actually shared by Kurds, Sunni Arabs, Christians, Turkmen, and Yazidis. “You had the vilayet of Baghdad, the Sunni area in Iraq,” Brownback added, oblivious to the fact that the region was so mixed, it contained all of the Shia holy cities and the city of Baghdad’s population was one-third Jewish in 1917. “You had the vilayet of Basra, the Shia state,” Brownback said of any area that had, Visser noted, “fewer Shiites than Baghdad and was politically dominated by Sunnis.”

Brownback’s completely misguided history of Iraq under Turkish rule concluded with his false claim that the provinces were “a three-state solution that the Ottoman Empire put in place as a way of managing these different groups who do not agree with each other, who do not get along.”

Marc Lynch, a professor of political science and international affairs at George Washington University, was similarly scathing in his analysis of the plan Biden pushed through the Senate that fall.

“By passing with 75 votes a meaningless, non-binding symbolic Senate resolution in favor of the partition of Iraq,” Lynch wrote on his blog at the time, “Biden managed to simultaneously: infuriate nearly all Iraqis, who have virtually unanimously condemned the resolution (as have the Arab allies of the US, for that matter); let Senate Republicans off the hook by allowing them to say that they voted for change even though they continue to vote against anything real; and endorse an unworkable plan which would massively increase human suffering while working against American interests in the region and not actually solving the problems.”

“I’ve never understood the appeal of ‘soft partition’ to anyone other than dedicated pro-Kurdish activists,” Lynch added. “It sounds like such a nice, clean exit strategy. But near as I can tell, it would actually mean heavy and active involvement of US troops in facilitating “transfer” of peoples (ah, how delicate that sounds) and a long-term military commitment to protecting the new entities (especially the Kurds). It would simultaneously exacerbate Shia-Shia conflict while enhancing Iranian influence in the Shia areas. It would infuriate the Sunnis who cling fiercely to the principle of a unified state and fuel the most radical trends in those areas while undermining more moderate leader. It would guarantee that the crisis of the internally displaced and refugees will never be solved, promoting instability in the country and the region for decades (while also rewarding sectarian cleansing strategies and encouraging them in the future).”

As Lynch suggested, what Biden, Gelb, and Brownback appeared to overlook was that in Iraq, as in Bosnia, ethnic and religious groups had spent centuries living together in intertwined communities, not in segregated regions. It was only possible to divide Bosnia into three regions after spasms of unbearably violent ethnic cleansing drove millions of people from their homes.

The main flaw of all partition plans is that those who draw them up implicitly accept the arguments of local segregationists, who claim that it is simply impossible for their people to live in peace with other ethnic or religious groups unless they have their own separate states — while ignoring the fact that people in these parts of the world had previously been living in relative peace for centuries in multiethnic, often very close-knit communities. When partition is enacted, interwoven ethno-religious groups no longer have to find ways to share power and live together, but are instead invited to drive their neighbors from their homes with threats and violence.

While Biden told voters that he and Gelb were simply applying the logic of the Dayton peace agreement that divided post-war Bosnia along ethnic lines to Iraq, the two men seemed oblivious to the flaws of that plan, and the ways in which it enshrined ethnic division achieved through brutal ethnic cleansing.

Before the wars in Yugoslavia began in 1992, very few people in Bosnia still defined themselves according to the religion of their forefathers — who were Muslim, Catholic (Croat), or Orthodox (Serb). After decades of communism, religious observance was casual at best and, for most people, what the three groups had in common, all being ethnic Slavs, was much more important than what distinguished them or their ancestors in the past. The population was so thoroughly mixed that on the eve of war, one-third of Bosnians had parents who were from two, rather than one, of the three groups, and demographic maps showing which group was the largest in any one part of the country looked much more like Pollocks than Mondrians, with swirls of colors splattered across most of the territory and almost no part of it being purely Serb, Croat, or Muslim. The country’s cities in particular were so mixed that there was no way that any one of them could have been assigned to one group or the other before the fighting began. And this is the important point: The fighting itself was almost entirely dedicated to tearing apart those mixed communities, to make it possible to draw lines between them, and to fence off one community from the other.

By accepting the segregationist logic of the nationalist warlords, the Dayton agreement also froze that division of the country along ethnic lines in place. “Dayton was an unqualified success in terms of ending the fighting. However, it enshrined the violent division of a country along ethnic lines,” Laura Silber, the author of “The Death of Yugoslavia,” told me in an email. “More than three decades later, Bosnia-Herzegovina still grapples with the legacy of the war, and of the Dayton agreement as well — which proved too complicated to implement and only enhanced the ethnic divide.”

Gelb’s first attempt to sketch out the plan for Iraq, published on the New York Times op-ed page in late 2003, was more open about the possibility that what he called “a three-state solution,” intended partly to punish Sunni Arab insurgents, could incite terrible violence and might require the U.S. military to oversee the mass transfer of civilian populations.

The first step would be to make the north and south into self-governing regions, with boundaries drawn as closely as possible along ethnic lines. Give the Kurds and Shiites the bulk of the billions of dollars voted by Congress for reconstruction. In return, require democratic elections within each region, and protections for women, minorities and the news media.

Second and at the same time, draw down American troops in the Sunni Triangle and ask the United Nations to oversee the transition to self-government there. This might take six to nine months; without power and money, the Sunnis may cause trouble.

For example, they might punish the substantial minorities left in the center, particularly the large Kurdish and Shiite populations in Baghdad. These minorities must have the time and the wherewithal to organize and make their deals, or go either north or south. This would be a messy and dangerous enterprise, but the United States would and should pay for the population movements and protect the process with force.

The eventual Biden-Gelb plan was particularly unpopular in Iraq. The month after it was first published, polling by the International Republican Institute found that 78 percent of the country disagreed with the proposed “segregation of Iraqis” — 66 percent “strongly” so — and just 13 percent agreed, with majority support only in the already autonomous Kurdistan.

The plan so tarnished Biden’s reputation, that in August 2008, when he was named Barack Obama’s running mate, Iraqis across the political spectrum reacted with dismay. “This choice of Biden is disappointing, because he is the creator of the idea of dividing Iraq,” Saleh al-Mutlaq, head of National Dialogue, one of the main Sunni Arab blocs in parliament, told Reuters that day. “We rejected his proposal when he announced it, and we still reject it. Dividing the communities and land in such a way would only lead to new fighting between people over resources and borders. Iraq cannot survive unless it is unified, and dividing it would keep the problems alive for a long time.”

“We don’t support establishing federal regions on a sectarian basis,” Kurdish lawmaker Mahmoud Othman added. “For example our region is not ethnic, it contains Kurds and non-Kurds. The regions should be established on a geographic basis.”

Ezzet al-Shabender, a member of Iraq’s parliament for the secularist Iraqi List led by former Prime Minister Ayad Allawi, even said that the widespread anger at Biden’s proposal had helped unite Iraqi lawmakers. “His project was the reason behind the unity of many political blocs that once differed in viewpoints,” he said. Shabender even compared Biden’s plan to the Balfour Declaration, the 1917 British promise to support the creation of a homeland for Jews in Palestine, which is seen as the most sever injustice of the colonial period.

Robert Ford, a diplomat in the U.S. Embassy in Baghdad at the time, told Akbar Shahid Ahmed of HuffPost recently: “Biden in 2006 looked at a really difficult and complicated Iraqi situation and tried to apply an overly simplistic solution.”

Ford, who is now a senior fellow at the Middle East Institute think tank, also blames Biden for helping to fuel the rise of the Islamic State when he decided, as vice president, to support the return of the sectarian Shia politician Nouri al-Maliki as prime minister in 2010. According to Emma Sky, who was the political adviser to Raymond Odierno, the commanding general of U.S. forces in Iraq that year, Biden seemed preoccupied with the idea of irreconcilable sectarian differences during a visit.

Odierno told Biden that the previously secular Maliki had become so sectarian and authoritarian that Iraqis feared him, and a secular leader would be more welcome, Sky recalled in her memoir, “The Unraveling: High Hopes and Missed Opportunities in Iraq.”

“I tried to explain the struggle between secularists and Islamists, and how many Iraqis wanted to move beyond sectarianism,” Sky wrote. “But Biden could not fathom this. For him, Iraq was simply about Sunnis, Shia and Kurds.”

As Sky pushed back on Biden’s belief that sectarian differences were the key to Iraq, she wrote: “He was clearly irritated by me. ‘Look, I know these people,” he went on. ‘My grandfather was Irish and hated the British. It’s like in the Balkans. They all grow up hating each other.'”

The result, as Reidar Visser observed in 2011, was a Maliki government “made up of mostly pro-Iranian Shiite Islamists,” with the secular Iraqiya Party, which had won a plurality of votes in the March 2010 parliamentary elections, sidelined.

“This Shiite Islamist government bodes ill for the country’s future,” Visser wrote presciently, before the rise of the Sunni Islamist group ISIS. “Instead of appreciating the intense struggle between the cleric Moktada al-Sadr’s sectarian Shiite followers, and moderate Shiites who believed in a common Iraqi identity, the Obama administration remained steadfastly focused on the Sunni-Shiite-Kurdish trinity, thereby reinforcing sectarian tensions rather than helping defuse them.”

“The problem with this kind of thinking is that it’s built on an Orientalist perception of Iraq as inherently riven with primordial conflicts, a picture that’s been inflated by Western media portrayals of Iraq since the US invasion in 2003,” the journalist Alice Su wrote in 2018.

“Sectarianism is obvious in Iraq,” Su added. “You turn on the television to hear political and religious leaders railing against ‘non-believers’ of different sects; you drive past myriad checkpoints belonging to sectarian militias; you speak with survivors of targeted violence – not only minorities who fled ISIS, but also Shia civilians targeted by Sunni militants, Sunni civilians tortured by Shia militias, Kurds attacked by Arabs, Arabs detained by Kurds, and Shabak, Turkmen, Yazidi, Kaka’i and other minorities caught in the claws of fighting or ethnic cleansing.”

What Biden and Gelb, like many American policymakers, appeared blind to was the way the U.S. invasion and occupation had helped this sectarianism to grow.

As Visser explained, the focus on sectarianism predated the invasion. In 2002, as the Bush administration was preparing for war, American officials suggested to exiled Iraqi opposition leaders “that new political institutions should reflect Iraq’s ethno-sectarian groups proportionally.”

“Crucially,” Visser added, “the focus moved beyond the primary Arab-Kurdish cleavage to include notions of separate quotas for Shiites and Sunnis. When Americans designed the first post-Hussein political institution in July 2003, the Iraqi governing council, the underlying principle was sectarian proportionality. What had formerly been an Arab-Kurdish relationship was transformed into a Sunni-Shiite-Kurdish triangle. Arabs who saw themselves first and foremost as Iraqis suddenly became anomalies.”

The impact of this sectarian system soon spilled out of the Green Zone. “In Baghdad, in 2003 or 2004, it was kind of impossible to say that’s a Sunni or that’s a Shia neighborhood,” Ghaith Abdul-Ahad, an Iraqi journalist who reports for The Guardian, noted in 2007. “Now we can draw a sectarian map of Baghdad right down to tiny alleyways and streets and houses. Everything has changed. As an Iraqi I go anywhere (not only in Iraq, but also in the Middle East), the first thing people ask me is: ‘Are you a Sunni or a Shia?'”

In the end, Biden’s plan to remake Iraq into three ethnically homogeneous states won over Republican senators and foreign policy commentators like Tom Friedman but failed to catch on with voters in Iowa, where he got just 0.9 percent of the delegates in the 2008 caucus before dropping out of the race.

Now that he’s back in the state, and in contention for the 2020 nomination, it remains to be seen whether his embrace of segregation as a principle for Middle East peacemaking might still come back to haunt him.

Biden’s campaign did not reply to questions about whether the former vice president still thinks his plan was a good idea, despite fears that it might have prompted an increase in violent sectarian cleansing and anger from Iraqis, or if he would seek to implement it as president.

Correction: Saturday, Sept. 7, 4:48 p.m. EDT An earlier version of this article misspelled the last name of the painter Jackson Pollock.