Saul Landau of the Institute for Policy Studies claimed ("Perspectives," March 26) that in 1980 a "Senate Select Committee to Study Governmental Operations with Respect to International Activity" had published a report about "myriad illegal and violent activities" carried out in this country, with the concurrence of the U.S. government, by foreign intelligence agencies. He further stated that the Senate report indicated that some of these agencies, which the United States had helped create through the CIA, were "leading practitioners of terrorism."

Landau's assertion of the existence and content of this official government document was designed to lend credibility to the central theme of his column -- namely, that the priority given to combating international terrorism by the Reagan administration could be a "double-edged sword" because the United States, in the name of national security, had itself promoted international terrorism.

Checks with the Senate reveal that no report of the type he described was published in 1980 and no committee with the name he gave existed. The official evidence cited as supporting his thesis is thus nonexistent.

The facts are as follows: In a project not formally considered or approved by the Senate Foreign Relations Committee (though Chairman John Sparkman gave Sen. George McGovern approval for it), two staffers, Michael Glennon and John Ritch, interviewed persons unknown about activities of foreign intelligence agencies in the United States. No hearings were held; no one was interrogated under oath, though the interviews were recorded. In January 1979 Glennon alone drafted a document, based on the interviews, that was not intended for publication, purporting to relate the operations of certain foreign intelligence services in this country. Later, while at the State Department for "clearance and correction," according to Ritch, it was leaked. The Post, on Aug. 9, 1979, made its contents the major page-one story and, before and after that date, published at least eight Jack Anderson columns based on it.

Saul Landau on April 2 told me he had seen a copy of the "full" report before an abridged version was published in 1980 with, he claimed, the "best parts" left out. This time he had a new name for the committee involved -- the subcommittee to investigate the acts of foreign intelligence services in the United States. According to Senate officials, no such committee existed in 1980. Landau also told me the committee had held hearings in 1979, which it had not, and that the "facts" in the report had been affirmed by the Justice and State departments. In fact, State Department spokesman Tom Reston emphasized on Aug. 9 that the document was merely a "draft," not a "final report," and said "we don't regard the conclusions of this draft report as accurate . . . we have fundamental disagreements with some of the facts and findings . . . we categorically deny that charge," and added that the department deplored the leak and had communicated its disagreements with the report to the Senate committee. Justice Department spokesman also challenged the report's accuracy.

Later that same day Landau wrote to me that, although he had seen a typeset copy of the report that was "scheduled for publication" (which it was not), he had subsequently discovered that "it was not in fact published . . . for a variety of reasons."

So now we know from Landau himself that the official report that made up his key "evidence" of U.S. support for terrorism was nothing but a draft paper prepared by a Senate staffer, a paper criticized and challenged not only by State and Justice spokesmen, but by then White House spokesman Jody Powell as well.

[Editor's note: Landau says that he learned, from Francis McNamara, only after publication of his Post article that what he had thought was a Senate report on the way to official publication had not in fact been published. He says he stands by the substance of his article.]

Informed Americans are aware that with their, congressional and White House approval, the U.S. military and CIA have provided training for the forced of many other nations in counterinsurgency and guerrilla warfare and in intelligence organization and operations, as is completely proper, to help them defeat revolutionary Marxist movements attempting to impose totalitarian rule on unwilling victims. mThat, however, is a far cry from training them "in the craft of terrorism."

When the U.S. Army trained American men for the Rangers in World War II and for the Special Forces in Vietnam, it did not become responsible for the few aberrational and criminal veterans who later used the knowledge and skills thus acquired to kill or maim their fellow citizens. Similarly, the United States is not responsible for -- because it cannot control -- what any foreign nation does with military forces or intelligence agencies it has assisted. It incurs no blame if those wielding power should use them for other than legitimate defense purposes.

Thus, even if Landau had produced evidence that some foreign intelligence agencies that had received U.S. help in the past were now actually "leading practitioners of terrorism" (his column contained none), his logic would be completely faulty in blaming this country for this.

The United States, working through the United Nations and bilaterally and multilaterally with many nations, has taken numerous steps to halt the spread of terrorism. Despite these efforts, it has grown alarmingly. Something more must be done.

Landau has in the past espoused positions of Castro who, intelligence services and scholars agree, is one of the world's leading promoters and exporters to terrorism. He is disturbed by the Reagan policy, which is a threat to the principal weapon Castro has been using in his efforts to take over all of Central America.

The Post should not have lent a hand to his citation of a spurious report to support his anti-U.S. message.