FIRST, the stuff about Zbigniew Brzezinski. It's tangy

and it bears directly on the question of former secretary of state Cyrus Vance's taste and fitness for adversarial proceedings. If he couldn't handle a colleague with a wobbly commitment to collegial parity and a readiness to make his own rules of bureaucratic engagement, then how could he handle the Russians? Vance in his memoir gets in some licks. For instance, he questions whether the national security adviser had the "complete grasp of the details" he needed for his normalization mission to China. There are other quiet cuts at Brzezinski's combativeness in bureaucratic dealings no less than in world affairs.

Clearly, Vance had trouble handling Brzezinski from the start. He failed to block the latter's proposal that National Security Council discussion papers go straight to Jimmy Carter without review by senior State Department or other agency officials. He lost out to "others"--read Brzezinski--when he urged the president to start out on arms control with Moscow by ratifying Gerald Ford's modest Vladivostok agreement rather than by shooting ambitiously--too ambitiously, it soon turned out--for deep cuts in arms. Vance won Carter's formal nod as his foreign policy spokesman, but Brzezinski horned in and Vance couldn't shut him off. This made Vance look flabby and kept him not merely from expressing but actually from conducting the foreign policy on which he and Carter had initially agreed.

Vance, with his squareness, his lawyerliness, his evident lack of relish for confrontation, was not a good public advocate for difficult times, although in the first two Carter years he did well enough on the inside, arguing for restraint and steadiness in dealing with Third World turbulence and Soviet pushiness alike. But the revolution in Iran and the Soviet invasion of Afghanistan tended to discredit that argument and cost him heavily in the battle to moor Carter's mind. He was not even invited into the room where the decision to launch the Tehran rescue raid was made. "Stunned and angry," he stayed on just long enough to offer his contrary opinion, and to have it rejected.

It is a notable feature of this workmanlike, orderly and dutiful record of his service that not even at this climactic moment does Vance say anything faintly introspective or interesting in a personal way about himself. Either he is old-fashioned and discreet, or simply unresponsive and uncurious. For that matter, he passes all too lightly over what one might expect to be the centerpiece of a secretary of state's memoir, his relationship with the president. I put the book down feeling that the Carter-Vance relationship had offered a certain Truman-Acheson potential --a populist president and his patrician adviser --but that it had misfired at both ends. An explanation is not here.

His book, packed as it is with interesting detail and organized around the big episodes, like SALT, the Middle East and Iran, does little to alter the common impression of Vance as an intelligent, thoughtful, disciplined, somewhat sentimental 1960s liberal who was prepared to be reasonable and who counted on others being basically reasonable, too. It was his misfortune to profess and project an allegiance to good international citizenship precisely at that post- Vietnam moment when the Soviets were testing the uses of their new power in respect to an uncertain United States and impressing an increasing number of Americans--finally, a majority, including Carter but not Vance--with the notion that they preferred their own rules.

Vance began and ended his service as secretary believing that foreign policy must be free from the pressures of the moment and from wide swings of public opinion. In fact these professions reflect Vance's essentially apolitical nature, his disdain for messiness and contention, and the peculiar ambivalence that still lies behind his conception of foreign policy.

By ambivalence I mean the sense Vance exudes of having more in common with his Soviet opposite numbers than with certain associates or with public opinion on the American side. The sense comes out strongest in the episode with which Vance chooses to open his book.

He is visiting Moscow in mid-1981 after Reagan's election, and he wonders whether such events as "the Soviets' brutal invasion of Afghanistan" and the American failure to ratify SALT--undifferentiated peas in his analytical pod--"had aged Gromyko and how frank (Gromyko) could be in discussing the wrenching issues that divided our countries. . . . I was genuinely pleased to see him again, as I believe he was to see me. . . . Gromyko said he wanted to ask me a question that was bothering him and a number of his colleagues: what does the future hold for U.S.-Soviet relations? There are some in the Soviet Union, he said, who would write off any hope for progress in the foreseeable future. I replied that that would be a grave mistake and a self-fulfilling prophecy. I said that I did not believe the final word has yet been said on the shape and texture of our bilateral relations, and it would be wrong to conclude that the stern rhetoric which had been appearing in Washington foreshadowed a total freeze in U. S.-Soviet relations. I said I certainly hoped that would not be the case and counseled patience."

We and the Russians do share a great common interest--preventing nuclear war. Vance labored mightily to serve that interest. His finest contribution was his work in negotiating SALT II--and in searching for peace in the Middle East and in Africa. The failure of the Senate to ratify SALT pained Vance deeply. His solicitude for the abstraction known as "U.S.-Soviet relations," however, was and is misplaced.

Politically, this abstraction dulled Vance's responses to the Kremlin's Third World adventurism and cost him first credibility, then control, and finally power. After the Soviets invaded Afghanistan--the event that exploded what was left of the administration's internal balance-- Vance wrote Gromyko, saying it was vital that "both of us give sober consideration to the implications of the current situation." His next thought was to meet with Gromyko "to reopen a dialogue." Carter wouldn't let him do it.

Vance never did go much beyond these inadequate expressions of earnestness in the way he addressed the vexing question of linkage: the management of Third World competition and arms control at the same time. Brzezinski argued fairly that Moscow was cheating on d,etente, taking it as a license to prowl. Vance said take it easy, calculating that sooner or later the locals would slough off Soviet influence on their own. Go with the Third World flow, he said, even with Khomeini.

Should American foreign policy be shaped assertively, unapologetically, as an exercise of "power and principle" (the title of Brzezinski's recent memoir) or more carefully, deferentially, in awareness of "hard choices" (Vance's title)? I await a memoir entitled "Making the Best of a Tough World," subtitled, "Bringing the American People Along." Our foreign policy is unavoidably made at the point where an uncertain domestic political debate intersects with a volatile international environment. The legitimacy of both must be acknowledged.

Vance had some good ideas: steady things down with Moscow, pay attention to the Third World, be fair and open. But these ideas could not carry Vance across the gap opened up by the turmoil in Washington and the world. His response was to restate his first premises. He was only being consistent, in that Moscow visit in 1981, when he accepted the terms of Gromyko's sly and provocative question about Ronald Reagan and commended patience, rather than restraint. The notion of a "liberal" foreign policy has yet to recover.

I read Brzezinksi's book before reading Vance's. The surprise is

that the differences between the two men in style and substance are so much greater than was even commonly thought. Had the finer qualities of each dominated--Vance's decency and sense, Brzezinski's intellectuality and feeling for power-- Carter would have been hailed for putting two unlikely but worthy partners into harness. As it was, Carter did not supply enough of the leadership and direction to pull off the difficult task he set for himself, and that leaves him primarily responsible for the heavy foreign-policy disappointments of his presidency.