KANAN MAKIYA's latest creative block seems as imposing as the concrete blast walls that have sprung up across Baghdad in the four years of war.
He is having trouble putting words to paper, grappling with a new book that he says is likely to be his final political work on Iraq.
"The thing that's difficult is the form of the book," Mr. Makiya said as he sat down one winter evening in his living room here. "I never had this problem before the fall of the regime. Things were simpler. The dictator was there, and you knew where you stood."
The dictator was, of course, Saddam Hussein, the target of Mr. Makiya's vitriol in a series of acclaimed books that he wrote on Iraq, beginning with "Republic of Fear," published in 1989.
Until the American invasion in March 2003, Mr. Makiya, an Iraqi-American born in Baghdad in 1949, was the leading intellectual voice crying out for Western and Arab nations to topple Mr. Hussein. He was a close friend of the Pentagon darling Ahmad Chalabi, and had the attention of neoconservatives. Vice President Dick Cheney praised him on "Meet the Press," and Mr. Makiya was one of three Iraqi-Americans who met with President Bush in the winter of 2003.
Those were simpler days indeed, before the endless waves of car bombings, before the thousands of Iraqi and American deaths, before the descent into chaos and sectarian violence that has driven liberal idealists like Mr. Makiya into bouts of hand-wringing over a single inescapable question: what went wrong?
Which brings us to Mr. Makiya's next book.
"I want to look into myself, look at myself, delve into the assumptions I had going into the war," he said. "Now it seems necessary to reflect on the society that has gotten itself into this mess. A question that looms more and more for me is: just what did 30 years of dictatorship do to 25 million people?"
"It's not like I didn't think about this," he continued. "But nonetheless I allowed myself as an activist to put it aside in the hope that it could be worked through, or managed, or exorcised in a way that's not as violent as is the case now. That did not work out."
HERE in this two-story Victorian house on a quiet lane south of Porter Square, the thing that "did not work out" seemed very far away. Mr. Makiya was awaiting the arrival for dinner of a former student of his at Brandeis University, where Mr. Makiya is a professor of Islamic and Middle Eastern studies. While musing about Iraq, he admitted his inability to foresee the manifold shortcomings in the American project.
"There were failures at the level of leadership, and they're overwhelmingly Iraqi failures," he said. Chief among the culprits, he added, were the Iraqis picked by the Americans in 2003 to sit on the Iraqi Governing Council, many of them exiles who tried to create popular bases for themselves by emphasizing sectarian and ethnic differences.
"Sectarianism began there," he said.
Mr. Makiya said he preferred not to name names. But it is well known that he had a falling out with Mr. Chalabi after Mr. Chalabi began courting Moktada al-Sadr, the radical Shiite cleric, in order to win support in Iraq's first national elections. For years before the war, Mr. Makiya had toiled with Mr. Chalabi to organize the Iraqi exiles who, despite disparate ideologies, stood united in their hatred of Mr. Hussein.
Then there is the small issue of American policy. "Everything they could do wrong, they did wrong," Mr. Makiya said. "The first and the biggest American error was the idea of going for an occupation."
At Brandeis, Mr. Makiya is exploring all these themes in a class this semester on — what else — post-invasion Iraq.
Because of the course, Mr. Makiya said he did not intend to work full time on the book until summer. For now, his days are consumed by his teaching duties and his obligations to the Iraq Memory Foundation, a nonprofit group he founded to record the brutalities of Mr. Hussein's rule.
In the living room, eight hard drives contain scans of some of the 11 million pages of government documents collected by the foundation. Mr. Makiya stumbled across some of the documents himself, in abandoned offices in Baghdad after the invasion. They range from birth certificates of Baath Party members to school records to military paperwork.
The foundation has shared some documents with the Iraqi court set up by the Americans to try Mr. Hussein and his aides. Yet, Mr. Makiya refers to Dec. 30, 2006, the day Mr. Hussein was hanged, as "one of the worst days of my life."
"It was a disaster, an unmitigated disaster," Mr. Makiya said, his voice rising. "I was just so upset, even on the verge of tears. It was the antithesis of everything I had been working for and hoping for."
The tribunal did little to expose the all-encompassing cruelty of the Baath Party, Mr. Makiya said. And in failing to control an execution chamber filled with seething Shiite officials and policemen, the Iraqi government "actually succeeded in making Saddam look good in the eyes of the Arab world."
He added, "Just like everything about the war, it was an opportunity wasted."
Mustafa Kadhimi, the Baghdad director of the Iraq Memory Foundation, said Mr. Makiya's faith in his homeland was wavering.
"When Saddam fell, Kanan started to discover many things he didn't have before in his mind," Mr. Kadhimi said one afternoon in his office inside the Green Zone. "Kanan is really shocked about what's going on the ground. He's starting to lose his hope that we can build a new Iraq, a real Iraq."
Last summer, Mr. Makiya, who studied architecture at the Massachusetts Institute of Technology, proposed a sweeping urban renewal project to Iraqi officials on a trip to Baghdad. The idea was to create, in the heart of the city, a pedestrians-only green space of several miles.
"You're talking about a massive rethinking of the city," Mr. Makiya said, waving his hand across a satellite map of Baghdad hanging on one wall. "Someone has to keep dreaming."
LIKE so many things in Iraq now, it would remain exactly that — a dream. Mr. Makiya had traveled to Baghdad intending to make his pitch to Prime Minister Nuri Kamal al-Maliki. But he met with lower-level officials instead. "There was terrible stuff going on in Baghdad," he said, "and one did not feel right making a full presentation."
The doorbell rang. Yoni Morse, Mr. Makiya's former Brandeis student, had arrived, stomping through the snow with a bottle of wine from Israel. The two sat down at the dinner table with Mr. Makiya's 12-year-old daughter, Sara, and his third wife, Wallada al-Sarraf. Spread before them were aromatic Iraqi dishes that Ms. Sarraf had cooked — chicken, rice, eggplant with yogurt.
Talk turned to the presidential race. Mr. Morse mentioned the pressure that Hillary Rodham Clinton was facing to apologize for her Senate vote authorizing President Bush to go to war.
Mr. Makiya stared into his glass of red wine. "That's so Maoist," he said. "People shouldn't feel the need to apologize. What is there to apologize for?"