One of Jimmy Carter's first acts after being elected president was to appoint a brilliant former White House adviser as the new director of the CIA, which was then so much in the limelight for its secret paramilitary operations and its covert fomenting of civil wars around the globe.

The appointee was Ted Sorensen, widely admired as President Kennedy's chief brain truster. The only trouble was that Sorensen had been a pacifist and conscientious objector, which affronted senators who thought the CIA should be run by a gung-ho type. Sorensen's confirmation never came to a vote, for he withdrew. He had not sought the job in the first place.

All this comes to mind now because the White House, having previously chosen a dove for a hawk's job, has just picked an army general to direct the Arms Control and Disarmament Agency (ACDA). The trouble this time is that the general, until a few weeks ago, belonged to an organization strongly opposed to the kind of strategic arms limitation agreement (SALT II) that the Carter administration has been working toward.

The appointee is retired Lt. Gen. George Seignious, currently president of The Citadel, a military academy. He also has been serving as a delegate-at-large on the SALT negotiating team since September 1977. He is regarded as an able, likeable officer, but not a conspicuously hawkish one.

Nevertheless, earlier this year Seignious joined the Coalitin for Peace Through Strength, a pressure group set up by the very hawkish American Security Council to "Stop SALT II" on grounds that the expected arms limitation treaty with the Soviet Union would "lock the U.S. into military inferiority."

The general now says he did not understand the aims of the organization at the time he became a member. He resigned from it on Oct. 17, several days after visiting the White House to discuss his ACDA appointment, saying in a letter, "I personally resent the distorted and untrue statements" about SALT in the group's literature.

John M. Fisher, president of the American Security Council and a prime mover in the anti-SALT coalition, says the letter of invitation to Seignious plainly stated that the group was out to "Stop SALT II."

Seignious, in turn, says the original correspondence got lost, and that he joined only after a followup letter in which he saw that the sponsors included famous people "like Moorer, Lemnitzer and Clare Booth Luce."

He was referring to Gen. Lyman Lemnitzer, former commander of NATO forces, and Admiral Thomas Moorer, former chairman of the Joint Chiefs of Staff. Luce is a former member of Congress and playwright. They are indeed famous, and part of the fame rests on their prominence as hardliners on defense questions.

The sponsors also include Maj. Gen. John K. Singlaub, who was forced into retirement for criticizing President Carter's military policies, plus Lt. Gen. Daniel Graham, former head of the Defense Intelligence Agency, and Maj. Gen. George Keegan, former head of Air Force Intelligence, both of whom charge that the administration is letting Russia achieve military superiority.

The American Security Council has been highly publicized for years, and front-page stories attended its launching of the Coalition for Peace Through Strength. It's not going to be easy for Seignious, at confirmation hearings, to convince senators that he had no idea what the organizations stood for, although it is also hard to believe that the general would knowingly join an anti-SALT group while serving on the SALT negotiating team.

The general has compounded his difficulties by his resignation letter, which he now thinks was "entirely too strong." Fisher agrees. He feels it raises questions about the general's fitness for a post that requires "a certain degree of reasonableness." Meanwhile, Fisher is circulating his correspondence with Seignious to the coalition's membership, which includes 175 members of Congress. So now the general has hawks as well as doves challenging his appointment; confirmation is not going to be smooth.

The anti-SALT forces on The Hill, emboldened by the defeat of five pro-SALT senators in the recent elections, are more confident than ever that they can block a new treaty, which calls for a two-thirds majority for ratification.

They may, however, have overlooked a hint that Hamilton Jordan dropped during a television appearance a few days ago. The President's close adviser quietly noted that Mr. Carter still has the option of submitting any new arms limitation pact as an executive agreement, which requires only majority approval.

Nearly everybody thinks that SALT I was a treaty, but actually it was simply a five-year interim agreement, expiring in October 1977. It has remained in effect during negotiations for SALT II by U.S. Soviet concurrence.

Arthur Cox,an arms-control analyst and author of "The Dynamics of Detente," believes Carter "should avoid a showdown in the Senate until completion of the next round of negotiations," which are expected to provide a ban on new nuclear weapons, plus substantial cuts of existing nuclear arsenals. "Only then," Cox says, "will the case for a new SALT treaty be compelling."