IN THE LONG and disgraceful Barbie affair, the role of the U.S. Army's Counter Intelligence Corps was central. What induced Army officers to hire a former Gestapo commander in the first place?

The CIC first came across Mr. Barbie in the spring of 1947, in a period when Washington was debating what kind of intelligence service the country needed and who should run it. There was a strong appreciation of the dangers in continuing covert operations, and President Truman had dissolved the Office of Strategic Services almost as soon as the fighting had ended. In early 1947 Congress was in the process of establishing the CIA, but at that point there was no clear concept of its functions. By that time the Army had been struggling for two years with the need for information regarding the country that it was occupying and the activities of the other occupying powers--not only the Russians but the British and French as well.

During the war, the CIC's job had less to do with intelligence than with routine security behind the lines. With the occupation, the political aspects of the job began to grow. Since bureaucracy, like nature, abhors a vacuum, many officers saw both a need and an opportunity to expand the CIC into a much more ambitious operation. But it was badly equipped for that. The Justice Department's excellent report on the Barbie case, published this week, makes this point clearly. Some of CIC's people had had experience in intelligence work, but not enough --and the commanders were military men with little preparation for the sinister world they were entering.

They needed trained people quickly. Where better to find them than among survivors of Hitler's highly efficient police and intelligence services? It is a token of the CIC's inexperience that it apparently never thought to look into these men's backgrounds. That is how a man like Mr. Barbie, the former Gestapo chief in Lyons, wanted there for a catalog of offenses that make the skin crawl, came to spend four years on an American salary--and that is why the CIC, when it finally realized his identity, chose to help him escape rather than face exposure.

The growth of the CIA made it unnecessary for the military services to remain in this kind of work for which they were manifestly unsuited. But the temptation to dabble apparently lingered on. One of the more dismaying disclosures in the Justice Department's report is the reference to a network that the Army was thinking of organizing in South America in the mid-1960s, for which it twice considered rehiring Mr. Barbie. The CIA eventually dissuaded the Army. The sheer witlessness of the idea is astounding.

The Army got itself entangled with Mr. Barbie through naivete, ambition and carelessness. But naivete, ambition and carelessness are not an adequate defense to the charge of obstructing justice-- not for Army officers, and far less for the government of the United States.