Nearly 40 years ago, I came across a useful snapshot of the creative, chaotic, consequential life that Edward Kennedy lived in the public square. It was somewhere in the bowels of the Senate office building that Kennedy made his headquarters for 47 years–a two-office suite inhabited by two remarkable people. The first office I walked into was run by a young, up-and-coming politician and lawyer whom those of us condemned to follow national politics had first noticed in Bobby Kennedy’s 1968 presidential campaign. On any given day, other pols and officeholders, favor-seekers, and would-be allies could be found in this lair, eager to do business with the man who even then was handling just about anything of a sensitive nature on Kennedy’s behalf: Paul Kirk.

Within another 20 years, Kirk would help arrange the senator’s divorce, play a role in the Democratic Party’s long march back from Reagan-era debacles, and then join his Republican counterpart, Frank Fahrenkopf, in a two-decade-plus reign staging the general election season’s presidential debates. In the end, the first true moment of comfort after Kennedy’s poignant death was the appointment of Kirk (by then the executor of his friend’s estate) to mind his Senate seat until a successor is elected.

In the office beyond Kirk’s sat Dale de Haan, a typically brilliant Kennedy hire from the then-fledgling human rights community and a person of remarkable intellect and diligence. He greeted a decidedly different kind of visitor: diplomats from all over the world, intelligence agents, human rights campaigners fresh from some torturer’s dungeons. De Haan ran one of Kennedy’s most important fiefdoms, the Senate Judiciary Committee’s subcommittee on refugees and immigration. This hitherto ignored unit turned out to be the mechanism that Kennedy used to oppose further escalation of the Vietnam War in 1967 and then move into opposition to the entire, mad enterprise. De Haan’s portfolio would eventually go global as he became one of the leaders in the office of the U.N. High Commission for Refugees, whose work would richly earn the Nobel Peace Prize in 1981.

Truth be told, there was nowhere in the Kennedy empire–from the mid-1960s right through last year–you couldn’t find workaholic geniuses toiling on the major questions of the day, most of them on their way to distinguished, high-profile careers. Part of the wonder surrounding what is easily the most significant legislative career in American history is that no matter which of these cubbyholes you stopped by over the years, you could pick up a thread that reached all the way back to the New Frontier and all the way forward to the present. Follow the threads that Kennedy directly dominated, from education and health care to immigration and income support, and the number of Americans directly affected easily surpasses 200 million, more than most presidents.

In his surprising, even stunning memoir completed just before his death this past summer, Kennedy hasn’t followed quite every thread; this is memoir, not autobiography. In 500 pages, however, he has managed to follow many of them, including the most complicated one of all–the tale of his own journey from privilege to power, from tragedy to tragedy to tragedy, and from wound to wound (more than one self-inflicted).

Introspection was never a Kennedy strength or habit, but True Compass has surprised and astonished those who knew him well. That includes me, a baby reporter in the late 1960s gleefully sucked into the vortex of Kennedy’s involvement in all the burning issues of his time. I dealt with him for 40 years in a happy evolution from quasi-student to willing accomplice on scores of causes (some hopeless, many successful) to something more personal; my real bias is that I never stopped being stunned by his work ethic, his relentlessness and diligence, not to mention his kindness. In the commercial-publishing trade there have been three similarly notable memoirs in recent years, each by a glass ceiling-shattering woman–Katherine Graham, Sandra Day O’Connor, and Madeleine Albright. Kennedy’s is their equal–another valuable contribution to understanding Americans of consequence who emerged after World War II.

The books all present an uncommonly thorough effort to understand or at least account for their emergence. In Kennedy’s case, I never got the impression that he thought his family’s size, clout, or wealth was unique or all that important to understanding him. He was hardly the only final child in a large family to play (in his words) catch-up to older siblings. In our conversations through the years, I did manage to sense the importance to him of his family’s closeness, its competitiveness, and the emphasis it put on relentless perseverance, all of which are prominent in his narrative and familiar to anyone with even a casual awareness of his life.

His memoir, however, sheds considerable light on aspects of his life–notably his childhood and his faith–that this extremely private person rarely talked about. The discussion of his childhood is loaded with stories about his father, and by comparison very sketchy about his mother (he notes almost in passing that she spent a good deal of time in Europe while he was a young boy in the 1930s). Perhaps because Joe Sr. was more of a presence in his childhood homes after having spent much more time away building his immense fortune before Kennedy was born in 1932, and because most of his siblings were older and beginning to make their own way in the world, Kennedy writes of an extremely close relationship, replete with constant instruction on elemental life lessons. Most revealing is his summary of Joe Kennedy’s sermons while he was still a non-serious adolescent, especially after he got bounced from Harvard for arranging another freshman to take a Spanish exam for him. His father made it clear he would always love him no matter his accomplishments or failures but he also made it clear he would be disappointed if he failed to use his good fortune and education to try to make a difference in the world as a serious person–the source of my favorite Kennedy one-liner, first used by John Kennedy in 1960: “All of us can make a difference, and each of us should try.”

More surprising is the importance of faith as a thread through the memoir. Here Kennedy’s remarkable mother looms larger:

Both of my parents were deeply religious and the family prayed together daily and attended mass together at least weekly. Yet it is Rose Kennedy, mainly, to whom I owe the gift of faith as the foundation of my life. It is a core factor in my understanding of who I am…[It is she] to whom I owe the gift of faith as the foundation of my life.

His “center,” however, was the social gospel, not rigid, theological doctrine. He and Robert Kennedy (whose devout faith is better known), as well as his father, were strong advocates of a less restrictive, more welcoming faith even in the years before Pope John XXIII initiated his celebrated reforms. In his words:

My own center of belief as I matured and grew curious about these things, moved toward the great Gospel of Matthew, Chapter 25 especially, in which he calls us to care for the least of these among us…It’s enormously significant to me that the only description in the Bible about salvation is tied to one’s willingness to act on behalf of one’s fellow human beings. The ones who will be deprived of salvation–the sinners–are those who’ve turned away from their fellow man. People responsive to the great human condition, and who’ve tried to alleviate its misery–these will be the ones who join Christ in Paradise.

Kennedy did not talk like that outside his family until this book. It is one reason so many people were stunned when parts of his letter to Pope Benedict were read at his gravesite. On one level, it was a Senator seeking a blessing from his Holy Father in a note hand-delivered by Barack Obama. But the words were those of a penitent on his deathbed seeking a prayer from his priest.

He is not shy or sparing in discussing his failings. From the moment he belatedly came forward the morning after he drove his car into Poucha Pond on Chappaquiddick Island off Martha’s Vineyard in 1969, some of the roughest adjectives, short of pure invective, ever uttered about his conduct have come from his own mouth. He is no less gentle on himself in his memoir, but the extent to which he sought to atone for Mary Jo Kopechne’s death is noteworthy. As he puts it in a particularly revealing passage:

But I could not wish it all away. I had suffered many losses during my life. I had lost all of my brothers and my sister Kathleen. My father had been lost to me in many respects because of his debilitating stroke. And now this horrible accident. But again, the difference this time was that I myself was responsible. I was driving. Yes, it was an accident. But that doesn’t erase the fact that I had caused an innocent woman’s death.

Atonement is a process that never ends. I believe that. Maybe it’s a New England thing, or an Irish thing, or a Catholic thing. Maybe all of those things. But it’s as it should be.

Compared to that horrible event, Kennedy’s discussion of his role in the collapse of his first marriage, his ex-wife Joan’s long struggle with alcoholism, and his own carousing and womanizing is by definition less important, but still notably candid.

The intense pain at the core of his life is of course what sets Kennedy apart. To lose all three of the brothers he idolized before he was 40, and all violently, as well as his sister Kathleen, and to see the horrible result of the brain surgery doctors mistakenly told his parents would improve the life his mentally retarded sister Rosemary, is a burden of unspeakable enormity; to then take responsibility for all of his brothers’ children and raising three of his own (the middle of whom lost a leg to cancer and years to painful, experimental treatments), all the while building an unequaled record as a national leader and senator, only added to the weight on his ample shoulders.

So much of the uninformed chatter about Kennedy makes it seem as if his life was one long saga of wretched excess. The truth is that the final indignity–his late-night hauling of son Patrick and nephew Will Smith to a bar in Palm Beach and the ugly tabloid mess that followed when Smith was accused, and subsequently acquitted, of raping a woman he met there–took place in 1991. That fall, after his embarrassing reticence during Clarence Thomas’ stormy confirmation hearings, Kennedy made a speech at Harvard that finally acknowledged that excesses in one’s personal life can affect one’s ability to function effectively in public life. His message was that he knew his excesses had, and that they never would again. For nearly the last 20 years of his life, they did not.

It is well-known that Victoria Reggie was in the audience that day (they had been going out for a few months by then). This pivotal event preceded their marriage by several months, but it was a decent metaphor for her impact on his life. He had been officially single for a decade after enduring what he describes as at least another decade or so of a for-the-kids marriage. But she not only completed him, she helped center and ground him. For 18 years he was obviously very happy. His portrait of her hard head and big heart, her fearless, playful sassing, and the natural aptitude of this product of major-league Louisiana politics for the Kennedy family business is touching and revealing. Kennedy never slowed down after Vicki Reggie became Vicki Kennedy, but his life stabilized and then gave him great satisfaction and happiness.

Kennedy entered the Senate when giants roamed its corridors, liberal, conservative, and centrist. He died in a very different time, dominated by smaller people more intent on slipping one-liners onto cable television shout shows than tackling great issues and problems. His career began when senators were almost universally expected to help govern the country, to work with each other, rather than immediately enter the next campaign. His career ended when partisanship and its evil twin, ravenous fund-raising demands, seemed all-encompassing and endless. Kennedy describes himself, though not in so many words, as a throw-back to the era when his unparalleled time on the scene began. To the end it remained his conviction that major steps forward were the product of a mix of passionate advocacy and backroom dealing only an alchemist could fully comprehend.

The country likewise changed. Entering the Senate at a time when liberal agendas dominated and dying when conservatism was suffering another crisis of legitimacy after years in the ascendancy, Kennedy was a devout long-view holder. As a freshman, he was a working-family Democrat who fought for civil rights and social liberalism and opposed the truculence and profligacy of the hard-line Cold Warriors; he wasn’t noticeably different in 2009. Nor did he believe that his ideas were out of step with the latest political trends; quite the contrary. But he did believe that only detailed perseverance could take a good idea forward and that tolerance for inevitable zigs and zags was an elemental character trait in the successful leader.

I do wish he had included more about his sense of how politics, issues, advocacy, and backstage maneuvering all combine in governance. He went, for example, from single-payer true-believer on health-care reform to builder on the chaotic foundation of the status quo, with scores of twists and turns along the way. In the process he had to deal with loud critics on the left as much as conservative obstructionists; often, Kennedy functioned as the liberal leader whom his peers trusted to tell them when to settle and for how much. As the country wrestles with the enormity and complexity of Barack Obama’s agenda, Kennedy’s absence is keenly felt.

Kennedy was not a natural pol, but in his diligent attention to detail he was very much his father’s son (and Jack’s brother). Joe Kennedy saw to it that he was introduced in depth to the tribal politics of Boston and then Massachusetts, while his brothers helped with his introduction to the nation and the world. He learned on the job, too: Kennedy recounts how, as a freshman senator in 1963, he avidly sought out the weird institution’s royalty. Back then, dealing with power in the Senate meant dealing with Southern Democrats, all of whom had supported segregation. Kennedy’s best and most entertaining example is his assiduous courting of the segregationist and pork-barrel Southern boss, Mississippi’s James O. Eastland, the chairman of the Senate Judiciary Committee. Kennedy provides a fall-down-funny tale of a morning with the cagey power-broker, during which Eastland gave him each subcommittee assignment he sought–but only after the bewildered freshman downed a glass of scotch for each favor. But Kennedy insists that he and Eastland eventually became friends (my memory exactly). His reasoning defines his approach to national leadership. “Then and always,” he writes, “I would work with anyone whose philosophies differed from mine as long as the issue at hand promoted the welfare of the people, and I would continue to await those better angels and to remain confident in ultimate justice.”

John Kennedy was no less willing, at least while President, to deal with rascals, and his knowledge of fellow politicians was encyclopedic. But the president was relatively detached and cool in his political work, doing what he felt he had to do, but without warmth. In contrast, his youngest brother loved politics, including its frequent absurdity, and he was loved in return, in ways that greatly enhanced his influence. He reminded me more than once that politics is a people business and that to make any kind of a difference it helps if you basically like people. He did.

Kennedy’s discussion of his role in national politics at a time of upheaval and transformation is more mixed. He provides a riveting account of the Vietnam period involving both his own growing opposition to the war and his brother Robert’s. He reveals that Robert Kennedy tried to get Lyndon Johnson to name him (Robert) the negotiator with the North Vietnamese and Viet Cong in Paris, a posting that would have removed him from the 1968 campaign. He also discusses at length his strenuous objection (aided by JFK assistant Ted Sorensen) to his brother’s belated decision to jump into that race, based on the view that it was the wrong year to take on an incumbent while the country was flirting with chaos.

What Kennedy does not do so well is acknowledge the connection between that stance and his own impulse to take on Jimmy Carter barely a decade later. Kennedy does name a few pols (mostly politicians no longer active in politics, like Hugh Carey of New York and the late Daniel Patrick Moynihan) who told him privately that he had to run for the Democratic Party’s sake but were nowhere to be found when he finally entered the race. But his sketchy account of the decision, and the failed campaign that followed, is unfortunate. There is more than enough detail to dispense with psycho-babbling theories that Kennedy’s heart was never in it (he went flat-out for nearly a year), but nowhere near enough to show that he spent too much time brooding about whether to run and too little planning the how and why of it.

In a memoir, inclusion and exclusion are tough decisions. There is more than enough narrative detail to give a general reader a true sense of the man, his life, and his work. And for more serious students and scholars, this is just the tip of the iceberg. Kennedy had already sat for days of interviewing for the oral history project at the University of Virginia (where he got his law degree), the transcripts of which should be available next year. His voluminous papers are already headed to the University of Massachusetts’ Boston campus. His family and friends are also getting the money together to establish an institute in Boston to support research on the Senate in American history. Kennedy was a diligent note-taker and diarist for roughly 50 years; over the years I have read some of these entries (on condition that I not quote them while reporting stories and columns), and they will be a gold mine of information about the man, his record, and the times. It’s sometimes forgotten how extensive his concern for history was; a long time ago, he made sure the historian Doris Kearns Goodwin received full access to his family’s papers during her research for the definitive study that became The Fitzgeralds and the Kennedys.

When Kennedy was diagnosed with brain cancer in the spring of last year, I remember thinking that the first casualty would be his memoir. I was of course dead wrong. Kennedy attacked the project just as determinedly as he attacked his disease and everything else he touched in public life. The result was well worth it, and that worth will only increase as time passes and the evidence of his gigantic contribution to the country accumulates.