Gen. Alexander M. Haig Jr., Ronald Reagan choice to be America's next secretary of state, has had an extraordinary career in public service, one that has repeatedly put him at the center of the biggest political storms of recent American history.

Although Haig is a controversial selection for the Reagan Cabinet, his career has given him one indisputable credential. The president-elect could have found only one other American with comparable personal experiences to take over the State Department. That other person is Henry Kissinger, whom the Reagan camp rejected as too controversial.

That Haig should be acceptable when Kissinger is not illustrates one of the general's most qualities, his ability to win the favor of other people. Those ultraconservatives in the Republican Party who rejected Kissinger made Kissinger's protege and former sidekick, Haig, their first choice for the State Department job. But he was also Kissinger's first choice. And Richard Nixon's. And Leon Jaworski's.

On the other hand, Haig is decidedly not the preferred choice of most Democrats in Senate. Senate Democratic leaders have already promised to closely scrutinize the Haig nomination before voting on his confirmation. The Democrats, though, are not the minority party; Republicans will control the full body and the Foreign Relations Committee, and may be able to push the Haig nomination through the confirmation process relatively quickly.

Because of his involvement in the Indochina war, the wiretapping at the beginning of the first Nixon administration, the Watergate affair at the end of the Nixon presidency and other controversial episodes, a thorough Senate inquiry into Haig's past would be a drawn-out affair. Reagan, however, has indicated a desire to swear-in his entire Cabinet on Inauguration Day, Jan. 20.

Today The Washington Post begins a series of articles on Haig's past, describing events that are likely to raise questions during the hearings and debate on Haig's nomination. In this installment, Haig's role in the Watergate period is reviewed.

Haig spent nearly 16 months as President Nixon's chief of staff. During that period, the White House devoted most of its efforts to defending Nixon from the charges of John Dean that he obstructed justice. Nixon spent long hours on his own defense during those months. But White House logs and accounts of dozens of former White House aides indicate that Haig spent even more time defending the president than Nixon did himself.

In May 1973, when Nixon realized that his two most trusted aides -- H. R. (Bob) Haldeman and John D. Ehrlichman -- were going to be forced to resign because of their involvement in the Watergate affair, he turned to Haig. The general had been Kissinger's deputy at the National Security Council for the first two years of the Nixon administration, and was Army vice chief of staff on May 4, 1973, when the White House announced that Haig would be an "interm" chief of the presidential staff.

Haig was a favorite inside the Nixon White House. Just a week before he was asked to take over Haldeman's job, Haig had been the subject of an approving conversation in the Oval Office between Haldeman and Nixon. The topic under discussion was apparently one of the sensitive episodes that fell under the "Watergate" rubric, the trial in California of Daniel J. Ellsberg, the man who leaked the Pentagon Papers.

Haig did a great job out there, Haldenman told Nixon, according to a previously unpublished transcript of the tape recording of this conversation made by Nixon's automatic taping device. Nixon agreed with this assessment of Haig's testimony at the trial, where the general had been used as a prosecution witness to rebut testimony offered in Ellsberg's defense.

At the time Haldeman and Nixon talked, they and Haig were three of a tiny circle of men who knew that the Nixon White House had ordered 17 wiretaps on government officials and journalists' private telephones in the early months of the administration -- a fact that finally became public knowledge five days later during the same Ellsberg trial. As a trusted confidant, Haig was unable to focus exclusively on policy matters as Nixon had hoped.

Instead, Watergate became Haig's preoccupation from the moment he arrived at the White House. One of his first acts was to ask the Pentagon's general counsel, J. Fred Buzhardt, to join the White House staff to deal with accusations against Nixon growing out of the Watergate affair. Haig, Buzhardt, lawyer Leonard Garment and Nixon's two principal speechwriters quickly went to work preparing a "national security" rationale for the wiretapping and other questionable activities that the president now acknowledged, including the so-called "Huston Plan" for illegal intelligence-gathering, the break-in at the office of Ellsberg's psychiartist and the order that the CIA tell the FBI to end its investigation of the original Watergate burglary.

The statement these men prepared, released on May 22, five days after the Senate Watergate Committee began its investigation, was intended to blunt Sen. Sam Ervin's (D-N.C.) inquiry and put Watergate to rest. It wes the first of numerous such efforts that Haig was to manage from his catbird seat in the White House.

The failure of that first effort could be attributed largely to John Dean, former White House counsel. Leaks to the press on June 3 tipped off Nixon and Haig that Dean planned to testify to the Senate committe that Nixon himself participated in the cover-up of Watergate. This news prompted Nixon to play back some of the tapes of his Oval Office meetings, and then to to discuss their contents with Haig (Haig was one of the handful of Nixon aides who already knew about the existence of the president's taping system).

This happened on June 4. Nixon and Haig conferred about the tapes eight different times during that busy day. Haig was coordnating the White House effort to use the tapes to create a selective account that would refute Dean's detailed testimony, which he had to construct from memory. In those June 4 conversations Haig learned from Nixon of what the president considered his "one problem . . . the dam conversation of March 21."

Nixon explained to Haig that he discussed clemency for Watergate burglars on that March 21 tape, a fact that the White House did not acknowledge for another 11 months. Nixon told Haig that this problem could be "well handled."

Five months later, after the existence of the president's taping system had been revealed, Haig was briefing Republican senators on Capital Hill, assuring them that the tape of that crucial March 21 meeting between Nixon and Dean was "exculpatory."

After three months of refusing to comply with subpoenas for White House tapes from both the Senate Watergate Committee and Special Prosecutor Archibald Cox, Nixon in October faced a court order to finally produce the recordings. At that point and Haig and Buzhardt proposed a "compromise." They suggested preparing edited transcripts of some of the subpoenaed recording and asking the venerable (and partially deaf) Sen. John Stennis (D-Miss.) to listen to them and affirm that the transcripts were a fair portrayal of the actual tapes.

Haig and Buzhardt went to Stennis to propose this arrangement, leaving him with the impression that the transcripts being prepared would be for the use of the Watergate Committee, not to satisfy a court, subpoena for the actual tapes. But Haig and Buzhardt hoped to persuade Cox and the court to accept the transcripts as well. (Had he known this, Stennis said later, he would have declined to play any role in the arrangement.) It was Cox's refusal to accept the Stennis plan that set off the "Saturday Night Massacre," another important moment that involved Haig personally.

On that October Saturday, Haig telephoned Attorney General Elliot Richardson and ordered him to fire Cox. When Richardson refused and resigned his post, Haig called Deputy Attorney General William Ruckelshaus and asked if he was prepared to dismiss Cox. The answer was no. r

"Well, you know what it means when an order comes down from the commander-in-chief, and a member of the team can't execute it," Haig told Ruckelshaus, according to his own subsequent account. Haig then asked Robert Bork, the solicitor general, if he would dismiss Cox, and Bork agreed to do it.

That night, teams of FBI agents sealed off the special prosecutor's offices on K Street NW, and at Richardson's office in the Justice Department, effectively impounding their files. At a press conference later, Haig said he personally had ordered the FBI to seal off those offices "because we had reports that members of the staff were leaving rapidly with huge bundles under their arms."

The furor caused by the Saturday Night Massacre persuaded the White House to agree to relinquish the subpoened tapes to Judge John J. Sirica's court, but not to the Senate committee. Almost immediately, however, Haig learned that no tapes of two of the subpoenaed conversations could be found, and that subpoenaed Dictabelt of Nixon's recollections of another conversation was missing.

Moreover, when Nixon was told that the Dictabelt couldn't be found, he had asked, "Why can't we make a new Dictabelt?" The President's willingness to manufacture evidence, Haig knew, had persuaded Nixon's two lawyers, Buzhardt and Garment, that Nixon had to resign the presidency. (A detailed account of this episode never disputed by any of the participants appears in The Final Days by Bob Woodward and Carl Bernstein.)

In addition, Haig learned at this time that Rose Mary Woods, Nixon's secretary, had said that she had inadvertently erased a four-minute section on one of the subpoenaed tapes, a section which White House Lawyers hoped (without knowing for sure) was not covered by the subpoena.

Despite all these problems, Haig launched a new White House offensive called "Operation Candor" in early November. This was an effort to persuade Congress and the public that there were no more startling, dramatic revelations still to come. In a series of nine meetings, Nixon, sometimes accompanied by Haig, met with 234 Republican members of Congress and 46 Democrats, telling them all there would be no more bomshells.

On Nov. 14, 1973, Haig learned simultaneously that the gap Woods had revealed actually lasted 18 1/2 minutes, and that this section of the tape was indeed covered by the subpoena. Haig waited a day -- a day on which Nixon met with another 78 congressmen to proclaim his innocence -- before telling the president about these new problems. A week later Operation Candor disintegrated in the furor provoked by the public acknowledgment of the 18 1/2-minute gap.

Haig was called to Sirica's courtroom to explain what had caused the gap. Haig said it might have been caused by an unexplained "sinister force" that had "come in and applied [another] energy source and taken care of the information on that tape."

At this same time, White House lawyers who had been listening to Nixon's tapes told Haig the full substance of that March 21 conversation which Nixon had told Haig in early June was a problem.

When Dean had told the president "we're being blackmailed," and that White House aides were perjuring themselves -- the lawyers told Haig -- Nixon asked Dean, "How much money do you need?"

"I would say these people are going to cost a million dollars over the next two years," Dean replied.

"We could get that," Nixon said. ". . . . I mean, you could get the money . . . you could get a million dollars. And you could get it in cash . . ."

Later in the conversation, the lawyers told Haig, Nixon had recommended continuing to pay the burglars' demands for "blackmail."

The White House reaction to the discovery of this conversation was to prepare a selective, heavily edited transcriptive of it. On Dec. 22 Haig took portions of this transcript to the Senate minority leader, Hugh Scott (R-Pa.), who had been urging release of the tapes. Haig said he would show this material to Scott provided the senator would never say that he had seen any tape transcripts. Scott agreed and started to read, but Haig insisted on leaving with the transcripts before the senator had a chance to finish them.

Later Haig supervised a much more extensive effort to prepare selectively edited transcripts of tapes sought by the House Judiciary Committee.

These were the transcripts that contained repeated gaps covered by the terms "expletive deleted" or material unrelated to presidential action."

On at least two occasions Haig sought to intervene on Nixon's behalf to influence the inquiries of the special prosecutors. In July 1973, Haig called Attorney General Richardson to make sure that Archibald Cox not extend his investigation into areas unrelated to the Watergate break-in, particularly including Nixon's finances.

The second instance occurred on April 30, 1974, when Haig called Deputy Attorney General Laurence H. Silberman and sought Justice Department support to limit the special prosecutor's (then Jaworski) grand jury investigation. Specifically, Haig sought Justice's help in acquiring internal memoranda from the special prosecutor's files that described dealings between Cox and Dean in 1973. The White House was looking for evidence that Cox had influenced Dean's testimony. Silberman refused this request and told Haig the "demand for internal memos from the special prosecutor's office" was "unprecedented."

On May 23, 1973, less than three weeks after he became chief of staff to Nixon, Haig called Secretary of the Treasury William E. Simon to ask the status of an Internal Revenue Service investigation of the president's friend Charles R. (Bebe) Rebozo. According to Simon, he checked and reported back to the White House that the IRS was interested in a $100,000 cash payment to Rebozo by reclusive millionaire Howard R. Hughes which Rebozo claimed was a campaign contribution to Nixon.

According to Rebozo in testimony to the Ervin committee, shortly after this he returned exactly the same $100,000 in cash to Hughes. Subsequently, Haig passed on to Rebozo's lawyer (according to the lawyer) information from a secret Federal Reserve Board study indicating that some of the hundred dollar bills Rebozo returned to Hughes appeared to have been issued after Rebozo said he originally received them from Hughes.

When Haig was subpoenaed to testify to the Ervin committee, he refused to answer questions, claiming a combination of executive privilege and attorney-client privilege, the latter on the grounds that he had been an intermediary between the president and his attorneys. Nixon instructed him to claim these privileges, Haig said.

Two weeks later, only after the Ervin committee rejected these claims to privilege, did Haig appear and testify on a few specific matters. However, Haig refused to answer questions -- as he has since -- about his broader role as the man Nixon depended on most during his last 16 months in office.