As details accumulate, the charges of corruption and cover-up fade away. Into the foreground comes the stark realization that the Carter administration showed the same ineptitude in handling Billy Carter that it demonstrates in managing great affairs of state. It is a case of Billygoat, not Billygate.

The corruption charge centers around the suspicion that favors were done for the Libyans, who paid the president's brother. But the Libyans did not get what they sought -- the release of Lockheed military transport planes or of Boeing commercial jets.

As to cover-up, Attorney General Benjamin Civiletti did warn the president that his brother might be in trouble unless he registered as a foreign agent. President Carter passed along the warning, and Billy registered. The White House and Civiletti subsequently made statements denying any contact between the Justice Department and the president on Billy's business. So there was an undoubted impropriety.

But not of a serious kind. The warning given by Civiletti eludes moral condemnation. A tenable view is that the attorney general has some responsibility to steer the president clear of legal difficulty. Letting the president's brother march out of sheer stubbornness into troubles he could legitimately avoid would have been a dereliction of that duty. Even in the post-Watergate climate, it is not the office of the attorney general to trap the president's brother.

Far from withholding information, moreover, the White House has been pouring it out of every door and window. It is entirely plausible that the first accounts were issued in ignorance of the exchange between the president and Civiletti. As soon as their conversation became known, it was divulged. The fault lay not in a cover-up but in hasty zeal to come completely clean.

That openness contrasts so dramatically with Watergate that the comparison works to Jimmy Carter's advantage. Indeed, the president's best chance of emerging unscathed from his present plight arises from the possibility that he can take arms against the Billygate charges, and smash them to smithereens in the Senate hearings.

The Billygoat charges present no such opening. Billy Carter obviously resents his successful brother. He constantly acts and talks in ways harmful to the president. He has had emotional troubles and has been hospitalized for alcoholism. He is, in other words, a problem -- but a well-defined problem.

The president and his family and his staff, however, have showed no capacity to deal with the Billy problem. Though it would have been easy and effective, they never told the Libyans to stop messing around with Billy, or else.

Instead of disciplining the younger brother, the president and Rosalynn Carter indulged him. State Department cables were made available to him in order, as Jody Powell put it, to "encourage good behavior." In the same vein, Mrs. Carter suggested to the president that Billy be asked to intervene with the Libyans on behalf of the hostages held in Iran. The president passed that suggestion on to his national security adviser, Zbigniew Brzezinski. Brzezinski arranged through Billy to meet an obscure Libyan diplomat, Ali Houdert. Houderi later met the president himself.

Those meetings were stupid to the fourth power. The United States, first, should not be asking favors of a regime as infamous as that of Col. Muammar Qaddafi. Second, the Qaddafi regime had -- for reasons including suspected murder and subversion -- terrible relations with the Ayatollah Khomeini. Third, if a conversation were still deemed opportune, it should have been undertaken by a professional diplomat -- not the president of the United States. And fourth, even if all the previous points are waived, the meetings should never have been arranged through that well-known problem child, Billy Carter.

So why did it happen? Because Jimmy Carter is an essentially weak president who does not deal with problems until they hit him in the face. Because when the president does focus, he communes with himself and his family more than working through the central mechanisms of government. Because when he does turn to the government, he relies on a staff composed largely of persons worshipful to the point of being unable to make sound judgments -- even in the president's best interest.

But those conditions not only underlie the Billy affair. They also explain how Carter messed up detente with Russia, mishandled the economy, panicked the Allies, alienated Congress and blew the support of the public opinion.

Billygoat, accordingly, expresses the innermost nature of the Carter administration. It feeds logically into the effort to dump Carter that is being merchandised in the form of a call for an open convention. That call echoes across the land, amplified by alarms and rumors, because the general climate of affairs renders Jimmy Carter vulnerable to the merest tremble of events. It is hard to see in that climate how Carter could win if nominated, or govern if elected.