In an overheated old schoolroom in Washington, Larry Wilkerson, a retired Army colonel, is doing his best to impose military discipline on 25 pupils as they prepare to attack a mountain of pizza, cupcakes and cookies. It is the year-end party for Macfarland Middle School's Colin L. Powell Leadership Club, a tutoring and mentoring program that Wilkerson oversees as a volunteer. Striding before his charges in smart burgundy suspenders, the colonel -- everybody here calls him the colonel -- makes a point about duty:

"If you're not attending the meetings, you aren't a member of the club. It's as simple as that." He rebukes a boy who has shown up for the party but otherwise been scarce. "You know how I'll feel if you don't come to subsequent meetings," Wilkerson warns, "and you don't want to get me angry."

Then he drops the bluff demeanor and authorizes the kids to start chowing down. "Try to keep as much as you can off the floor," he says in a Southern accent softened by frequent chuckles. For the next hour he circulates through the room, greeting each student by name -- Jamie, Angela, Trevon, Tanya -- encouraging them to keep their grades up, prodding them to complete their community-service projects, inquiring about sometimes precarious home lives.

Since 1998, Wilkerson has devoted himself to helping at-risk children at Macfarland in the name of Colin Powell, whom he refers to as "my boss" and "the general." Wilkerson works tirelessly to keep them in the club and to secure scholarships for them at private high schools.

Yet these days he and Powell are estranged: This program represents the last remnant of a long, deep friendship between them. Like ex-spouses in an uneasy detente, "we decided we'd just communicate over the kids," says Wilkerson, sounding pained by the situation.

The split came as both men left the administration -- Powell as secretary of state, Wilkerson as his chief of staff -- after working side by side for 16 years. Wilkerson, a once-loyal Republican with 31 years of Army service, has emerged in recent months as a merciless critic of President Bush and his top people, accusing them of carrying out a reckless foreign policy and imperiling the future of the U.S. military.

"My wife would probably shoot me if I headed to the ballot box with a Republican vote again," he says. "This is not a Republican administration, not in my view. This is a radical administration."

Wilkerson calls Bush an unsophisticated leader who has been easily swayed by "messianic" neoconservatives and power-hungry, secretive schemers in the administration. In a landmark speech in October, Wilkerson said: "What I saw was a cabal between the vice president of the United States, Richard Cheney, and the secretary of defense, Donald Rumsfeld, on critical issues that made decisions that the bureaucracy did not know were being made."

He is particularly appalled by U.S. treatment of enemy detainees, counting at least 100 deaths in custody during the course of the war on terrorism -- 27 of them ruled homicides. "Murder is torture," he says. "It's not torture lite."

As for the invasion of Iraq? A blunder of historic proportions, he believes.

"This is really a very inept administration," says Wilkerson, who has credentials not only as an insider in the Bush I, Clinton and Bush II presidencies but also as a former professor at two of the nation's war colleges. "As a teacher who's studied every administration since 1945, I think this is probably the worst ineptitude in governance, decision-making and leadership I've seen in 50-plus years. You've got to go back and think about that. That includes the Bay of Pigs, that includes -- oh my God, Vietnam. That includes Iran-contra, Watergate."

Such a critique, coming from a man who was long thought to speak for Powell, is seismic in Washington power circles. Some observers used to regard Powell and Wilkerson as so close that they enjoyed a "mind meld," but now Powell distances himself from the pronouncements of his former aide.

Often described as the ultimate loyal soldier -- and, like Wilkerson, a Vietnam combat veteran -- Powell has largely kept his mouth zipped. Whatever public regret or private disappointment Powell may have about selling the Iraq war, he still supports the commander in chief -- most recently during the flap over domestic electronic eavesdropping -- and occasionally dines with Bush.

Now consulting in the private sector, Powell declined to answer questions about Wilkerson's version of episodes in their tenure together. "General Powell considers Colonel Wilkerson a good friend of 16 years," an aide said by e-mail. "He has no other comment."

Powell did address Wilkerson's central charge of secretive White House decision-making in an interview with the BBC in December. "I wouldn't characterize it the way Larry has, calling it a cabal," Powell said. "Now what Larry is suggesting in his comments is that very often maybe Mr. Rumsfeld and Vice President Cheney would take decisions in to the president that the rest of us weren't aware of. That did happen, on a number of occasions."

The White House offered no specific rebuttal of Wilkerson's views, but a spokesman gave a statement taking issue with the notion that Bush was somehow misled about the need to invade Iraq (a charge Wilkerson hasn't made outright). "President Bush made his decision to go to war in Iraq based on the intelligence given to him by the intelligence community. It was the president's decision, and the president made that decision based on the totality of the evidence presented to him," said the spokesman, who asked that his name not be used "because of the nature of the topic."

Interviewed by CNN in November, Rumsfeld termed the suggestion of a cabal "ridiculous" and said of Wilkerson, "In terms of having firsthand information, I just can't imagine that he does."

Making a Military ManWilkerson, 60, got his start with Powell as a speechwriter and you can see why. He tends to talk in fully formed paragraphs. Over a lunch of barbecued chicken salad, he begins his life story this way: "I was born in Gaffney, South Carolina, which is right near Spartanburg, which is right near Greenville. My dad was a World War II vet -- B-17 bombardier and navigator. He came home from the war and entered the South Carolina National Guard, so I kind of grew up riding around in Jeeps and shooting .30-caliber machine guns. I shot my first Browning .30-caliber at 9. That is to say, the National Guardsmen made me think I was shooting it."

The family later moved to Houston, where Wilkerson graduated from high school. (Aside here on George W. Bush: "I see hard-headedness, I see arrogance, I see hubris, I see what I saw in a lot of Texans.")

Wilkerson went north to study philosophy and English lit at Bucknell but quit college in his senior year. He was newly married yet determined to go to Vietnam. It was 1966.

"I felt an obligation because my dad had fought," he says, "and I thought that was kind of your duty."Eventually he got there as an Army officer, spending a year in what he calls the "hottest combat" possible, piloting his OH-6A helicopter close to the jungle canopy, scouting out the enemy on behalf of the infantry.

"We got shot at nearly every day," he says. A brush with death came when a sniper's bullet pierced the helicopter's cockpit plexiglass, but he was never wounded or shot down. "My men used to call me the Teflon guy. . . . I felt like I had some kind of protective coating on me because I think I flew about 1,100 combat hours, which is a lot of hours."

(Predictable aside on hawks like Dick Cheney, Richard Perle, Douglas Feith and Paul Wolfowitz: "None of these guys ever heard a bullet go by their ears in combat.")

After Vietnam, Wilkerson went on to the elite Airborne and Ranger schools, earned his bachelor's in English literature and advanced degrees in international relations and national security. Rising through the ranks, he attended the Naval War College in Newport, R.I., and eventually returned there to teach. He later served as acting director at the Marine Corps War College at Quantico.

He made a natural professor. In conversation, he often lectures in a lofty but folksy way, citing the works of the great war theoretician Karl von Clausewitz or putting the zeal of neocons in historical context: Their fellow travelers, he says, were Lenin and the Bolsheviks and the Jacobins of the French Revolution -- utopians who had no qualms using the guillotine in service of their ideals.

(Long aside on how Bush, who criticized "nation building" as a candidate in 2000, became a globe-changing Jacobin: "Here we are with a failure in Iraq, a massive failure. Not only an intelligence failure, but it looks like it's gonna be a real failure on the ground. How do you suddenly transform that? Well, you suddenly become a Jacobin yourself, you're suddenly for this messianic spread of freedom and democracy around the world. You're suddenly an advocate of all things that John F. Kennedy was an advocate of: 'We will bear any burden, pay any price.' You've discarded John Quincy Adams, who said we're the friends of liberty everywhere, the custodians only of our own. And you've suddenly said, 'I'm the custodian of the whole world's liberty, and by God if you don't realize it I'm going to bring it to you -- and if I have to bring it to you at the point of a gun, that's the way I'm going to bring it to you!' ")

But back to the biography: Wilkerson spent years in Korea, Japan and Hawaii, assigned to the Navy's Pacific Command, where he burnished his skills as an executive assistant to the top brass.

"He's the most competent Army officer I've ever worked with," says retired Lt. Gen. James W. Crysel, one of Wilkerson's bosses at Pacific Command. "He could run a large corporation."

Retired Rear Adm. Stewart A. Ring, whom Wilkerson served for three years, is similarly effusive: "He is the most principled individual I have ever met and ever worked with. He is a remarkable guy with essentially no ego. He stands up for what he thinks is right -- not for Larry Wilkerson, but for what is right."

Such high praise won him an interview with Powell in early 1989, when the general was exiting as national security adviser in the Reagan White House and heading to Army Forces Command in Atlanta. Wilkerson says he was happy where he was, teaching at the Naval War College, and that evidently impressed Powell: "He said he didn't like overly ambitious people, and it was clear that I was content doing what I was doing and I wasn't really politicking for a job with him."

(An aside on Powell's personality: "He can be the most endearing person you'd ever want to meet in your life. The next minute he can be colder than fish.")

Powell's ConfidantIt was, as they say, the start of a beautiful friendship, spanning Powell's stint as chairman of the Joint Chiefs, the Persian Gulf War, the general's return to private life -- during which he launched America's Promise, the nonprofit initiative that seeded the Macfarland school project -- and Powell's support for candidate Bush and appointment as secretary of state.

Powell has long been known as a "reluctant warrior." Before the 9/11 attacks, he took the view that 10 years of U.N. sanctions had contained Saddam Hussein and expressed skepticism that Iraq had any ability to use weapons of mass destruction.

Having prepared Powell's testimony and speeches, and having received top-level intelligence briefings, Wilkerson also knew the post-9/11 case against Hussein was not airtight. Powell "presented a number of alternatives to war," Wilkerson recalls. "Those alternatives did not entail the use of force, or they did not entail the use of force immediately. And when he was made aware of the decision otherwise, he became the good soldier that he was. I know how he operates and he would have decided, 'Okay, I lost, and now I'll carry out the decision as best I can' -- and make it seem like it was his decision."

Powell's office on the State Department's sixth floor had a private door that led directly to Wilkerson's office. One particular visit burns brightly in Wilkerson's memory: It was November 2002, after the U.N. Security Council voted 15-0 to order Iraq to admit weapons inspectors, and Powell was in a contemplative mood.

"He walked into my office, and he said to me, musing and looking out across the greenery there toward National Airport -- I wrote it down on my calendar, that's the reason I know what he said -- 'I wonder what will happen if we put half a million troops on the ground, and scour Iraq from one corner to the other, and find no weapons of mass destruction?' And he left that rhetorical question hanging in the air as he went back into his office."

Bad InformationWilkerson, as it turned out, became the point man for making the case for preemptive war against Hussein. He put together the task force that, during a week at CIA headquarters, vetted all the intelligence reports used for Powell's famous pro-war presentation in February 2003 to the Security Council, where he brandished a vial of fake anthrax, played excerpts of intercepted Iraqi military chatter, and warned of mobile bioweapon "factories" and other doomsday machines, none of which actually existed. How did it happen?

"Larry thought they had cleaned out the obvious garbage, but it turned out there was more," says James A. Kelly, a former assistant secretary of state who's known Wilkerson for 20 years. "Larry felt that he let down the secretary, but the job was so big in cleaning out the misinformation."

Wilkerson won't say outright that he and Powell were deliberately snowed by intelligence reports tailored to fit a political push for war, but he has edged closer to that view, noting, "I've begun to wonder." It turns out that the administration relied on fabricators' claims about Hussein's illusory WMD programs and, in one case, an al Qaeda suspect whom the CIA turned over to alleged torturers in Egypt.

"I kick myself in the ass," Wilkerson says. "How did we ever get to that place?"

The speech tarnished Powell's gold-plated reputation, but he has never publicly pointed a finger at then-CIA Director George Tenet or the White House.

"Nothing was spun to me," Powell told David Frost in a BBC television interview last month. "What really upset me more than anything else was that there were people in the intelligence community that had doubts about some of this sourcing, but those doubts never surfaced up to us."

Why didn't the doubts reach Powell? Perhaps because then he wouldn't have given the speech at all?

"That's right," Wilkerson says, shooting a hard, solemn stare across the restaurant table. "That's right."

He also says, "I am prepared to entertain the idea that they used him."

Leaving the FoldBy early 2004, it was clear to Wilkerson that the Pentagon's failure to prepare for the war's aftermath -- including dismissal of Army Gen. Eric Shinseki's warnings as well as peacekeeping and nation-building plans -- had led to mounting deaths and injuries for U.S. ground troops. Nor was there, in Wilkerson's view, any thought given to future replenishment of the Army and Marine combat troops as the insurgency continued.

"Larry Wilkerson is a man of the Army in the finest sense," says Kelly. "He cares deeply about the U.S. Army . . . and he hates to see this institution badly damaged, and he believes it has been badly damaged."

Revelations about Abu Ghraib and the skirting of the Geneva Conventions added to Wilkerson's anger. He came to see Powell as the administration's lone voice of reason -- but Powell was being shut out.

"Combine the detainee abuse issue with the ineptitude of post-invasion planning for Iraq, wrap both in this blanket of secretive decision-making . . . and you get the overall reason for my speaking out," Wilkerson says.

"It never became personal for Powell, because he believed in the process," says Robert Charles, a former assistant secretary of state who worked with both men. "I believe it was harder for Larry, because he felt such great empathy for the boss, the most seasoned military officer he had ever served with."

(Another aside from Wilkerson, on this period with Powell: "I can say in all truth that in 16 years he never blew his stack. He got mad at me one time and asked me to leave the office -- told me to leave the office -- and that was towards the end when he was truly embattled, embittered and besieged, in my view. And even though it made me a little angry, I didn't take it that seriously because I knew at that point he was not a happy camper.")

Wilkerson went so far as to draft a letter of resignation to Bush. He never sent it and now wonders whether he should have come out guns blazing before the 2004 election. But becoming a vocal political defector in Washington can mean lonely exile, a loss of stature and income.

"I know it's very hard to put kids, job security and all that sort of stuff aside. I think that's the answer to why more people don't speak out."

For Wilkerson, there was another reason: It might seem a betrayal of Powell, his hero, the man who signed photos to him with sentiments like, "To LW, You're the greatest!"

Larry and Barbara Wilkerson, married for 39 years, live frugally in a Falls Church townhouse. She works at a Hallmark card shop. Their son is an Air Force navigator who's done duty in Iraq and Afghanistan, and their daughter, now a homemaker, served in the Army. Departing from government after Bush's second inauguration, Wilkerson had to decide: Would he speak his conscience or remain the quiet man like Powell?

"My wife said to me: 'You have two choices, my man. You can think more about him or you can think more about your country. I suggest you do the latter.' "

The Most Important ThingsFor years Barbara Wilkerson, 55, has baked cupcakes and cookies for the kids in the Powell club at Macfarland. After distributing treats at the year-end party, wearing her festive red blazer and a rhinestone teddy bear pin, she sat down for a moment to talk about her husband.

"The most important person in his whole life has been General Powell," she says. "And the general has never let him down."

Even more important than Barbara Wilkerson?

"Well," she hesitates, unsure how to put it. "When you're married to an Army person, the Army is always -- that's kind of the thing. But he wouldn't put anybody above his country, that's for sure."

She and others who know Wilkerson well say he has no intention of cashing in as a Bush critic. He hasn't joined a think tank or become a cable news pundit-for-hire. He has turned down publishers who want him to write a tell-all book for big money.

Wilkerson says he may write an academic text about presidential decision-making. This month he began supplementing his retirement with part-time teaching jobs at George Washington University and the College of William & Mary.

Recently a speakers bureau called Wilkerson to ask what fee he would want for a speech to a corporate audience. "I said I'd speak for the highest fee they'd pay," he recalls.

But there was a condition: The money couldn't go to him. He said he wanted it all donated to scholarships for children in the Colin L. Powell Leadership Club.

After the party the colonel helps with the cleanup. He lugs a bag of garbage out the door. All part of his duty.

Walking to his car, he offers a final aside, about poetry. The colonel sometimes uses poems to tutor the kids in reading. He mentions a line that Powell always liked because it described the depth of family ties:

"Home is the place where, when you have to go there, they have to take you in."

"In fact," says Wilkerson, "one time he quoted it to me and I said, 'You know where that came from?'

"He said, 'Yeah, it came from me.' I said no, that's from Robert Frost's poem."

Powell may or may not have known that already. The poem is called "The Death of the Hired Man."