The Last of the White-Tie Journalists : I’VE SEEN THE BEST OF IT: Memoirs, <i> By Joseph W. Alsop with Adam Platt (W. W. Norton: $29.95; 495 pp.)</i>

Celebrated journalists generally fall into one of two categories. There are the crusading outsiders, with their sharp investigative quills, who are eager to expose the powerful, comfort the afflicted and afflict the comfortable. Then there are the cozy insiders, rubbing elbows at all the right tables, who have intimate access to those in power and can write with the tone of authority that comes naturally to columnists whose phone calls never go unanswered.

Joseph Alsop, although often critical of the policies and politicians of his time, was the epitome of the latter. Indeed, he looked upon himself as more of an insider and member of the elite than most of the politicians and even Presidents whom he covered.

During his cantankerous four decades in journalism, Alsop was among the most influential and occasionally the most reviled newspaper columnists in America, and he eventually became the longest-lasting. He was socially snobbish and intellectually stubborn, but he was also a dogged reporter and a prose crafter of Latinate elegance.

Above all, he was an imperious member of the Yankee aristocracy or, as he liked to call it, the WASP Ascendancy. “I cannot make any sense of the pattern of my life, nor do I think anyone else can, except by taking note of the trifling-seeming fact that I began as a minor member of this now-vanished group,” he writes in his surprisingly amiable memoirs, which were edited by journalist Adam Platt and published three years after Alsop’s death.

His attachment to this social class was all the more eager because he did not, deep inside, feel fully a part of it. An offshoot of the Oyster Bay Roosevelt clan, Alsop’s family was not financially well off; in addition, he was an obese and awkward young man at Groton and Harvard. Thus he spent much of his childhood with his nose pressed to the glass, wistfully observing the easy charm and grace that came naturally to his more privileged friends and relations.

Through family connections, Alsop got a job on the New York Herald Tribune just out of college in 1932, and he was soon dispatched to Washington, spending one of his first New Year’s Eves there in the White House with his cousins Franklin and Eleanor. He quickly became a part of, and would remain so for more than half a century, the Georgetown social circle distinguished by its frequent and formal dinner parties.

The most entertaining parts of his memoirs--perhaps not totally by intention--are his copious discourses on the manners and style of this crowd. Of its mainstay, his cousin Alice Roosevelt Longworth, he writes that she “had a thousand stories about the Washington past, most of them very funny.” The same could be said of Alsop, though whereas her bons mots were generally tart and tangy, his tend to be vinegary and even acidic.

As a bachelor, and much later when at age 50 he married Susan Mary Patten, the vivacious widow of his best friend, Alsop hosted the most power-conscious dinner table in Georgetown. In doing so, he devised what he called “the bore factor,” which stated that a good dinner can abide only “half a bore” per every 10 guests: “The bore factor is important in Washington because most dinner guests there wish to see men in high office. . . . I count as half a bore a very dull but powerful man or a very stupid but pretty woman.” Alsop threw such dinners, often with Mrs. Longworth as an ornament, for professional as well as social purposes. “I know that whenever I go to Joe’s for a dinner party I am working for him,” she commented in later life. “I know Joe uses me. Good heavens, he uses everybody!”

The foundation of Alsop’s political philosophy was the need for America to contain communism. Along with his Establishment brethren, such as Dean Acheson and Robert Lovett, he became a fervent Cold Warrior and advocate of a strong defense. But he was among the earliest and bravest to denounce the bullying tactics of Red-hunting Sen. Joseph McCarthy.

As Alsop realized, McCarthy was engaged not just in a crusade against communism but in one aimed also at the East Coast social elite. For Alsop, like Acheson and others, the bonds of class loyalty came into play. “It was proof of the nastiness of that period that I was repeatedly asked why on earth I testified for Jack Service and John Davies (two foreign service officers hounded by McCarthy) when I had disagreed so flatly with them,” Alsop writes. “The obvious answer, which people in the McCarthy camp found difficult to understand, was that even though I did not always share their opinions, they were friends of mine, and I had never had the faintest doubt about their loyalty to their country.”

Alsop’s dedication to defanging McCarthy led to one of the most fascinating tales in his memoirs. He was aghast that President Eisenhower was reacting in so feckless a manner, so he dug up the names of people who served on the general’s occupation staff in Germany and on the governing boards he created, some of whom had been Communists, and brought this list to Eisenhower’s White House staff chief, Sherman Adams. The implied threat was clear: Unless the President stood up and fought McCarthy, Alsop would feel compelled to publish the list. Replied Adams: “Alsop, we’ll fight.” Eisenhower then took on McCarthy, which helped lead to the senator’s downfall. Of his role in egging the President on, Alsop writes: “I am proud of it to this day.”

For a reporter to be so involved in shaping events, rather than striking the standard pose of journalistic detachment, was unusual even back then, though not for Alsop. He believed that he had the right, even the duty, to be a participant as well as an observer in the politics that he covered. The most blatant example was when he became enthralled with John Kennedy and set out to help him become President. At first, the young senator regarded the columnist as an old fogy and shunned his dinners because no young women were ever there. “I explained that it was difficult to combine young girls with the kind of key figures in the Washington political scene whom I normally invited to my house,” Alsop recounts.

Eventually, however, Kennedy realized that he could benefit from the adulation of the town’s preeminent columnist, so he began a wildly successful courtship of Alsop. By 1958, Alsop had “resolved to help him in any way possible to win the presidency,” as he notes in his memoirs, adding unapologetically: “By the strict laws of journalistic propriety, I suppose this decision was improper.”

Alsop became an honorary member of the Kennedy clan. When he arrived in Wisconsin to cover the 1960 primary there, he went directly to the hotel suite of his pals Jack and Jackie to share a bottle of champagne. He then traveled with the campaign’s pollster Lou Harris to West Virginia, a critical test of whether Kennedy’s Catholicism would prove politically fatal. Meanwhile, he was writing columns on what he called “the prejudice issue,” denouncing those who would make Kennedy’s religion an issue.

Alsop’s memoirs end with the Kennedy years, the social and professional climax of his career. Thus the reader is spared reliving his controversial and unpopular final decade as a columnist, from 1964 to 1974, when he became increasingly strident in his support of the Vietnam War. With the proper balance of kindness and candor, his collaborator Adam Platt describes this period in an epilogue.

Alsop was ill-suited to the era of Vietnam withdrawals and Watergate exposes. His brand of access journalism and elitist sentiments--just like the white-tie dinner parties he so relished--fell out of fashion. But his account of a bygone cozier era, complete with finely wrought dry points of quirky personalities and social customs, has the charm and grace of a Henry Adams tale. For Alsop was, for both better and worse, a willful anachronism who took great pride in being among the last of a dying breed.