Jonathan Randal tries again in his most recent article {May 31} -- the latest in a series about Tunisia -- to discredit Tunisia's leadership by blaming President Bourguiba for "radicalizing" an otherwise "indigenous" and "moderate" fundamentalist movement.

Backed by the unimpeachable authority of anonymous sources, Randal bases his commentary on a slightly severe prediction: Tunisia's fate is sealed as it faces an uncertain future, or -- as it was so soberly put in the headline -- the country "is on the brink" of some sort of apocalyptic disaster.

But for Tunisians who have seen and heard worse in their long history (from Cato's repeated calls for the destruction of Carthage to the more recent threats from the land, sea and skies of the Mediterranean), Randal's alarmist tone is unconvincing.

It might be useful to recall what was written in The Post by John K. Cooley, a respected analyst, who, as early as Oct. 6, 1981, explained how "Tunisia moves to contain a wave of Islamic fundamentalism."

Cooley stated that "During the '60s and the '70s, many young Tunisians thought it fashionable to be Marxist or leftist; now the new radical chic is Islamic." He quoted Rached Ghannouchi as preaching to his followers in a loud and clear voice: "the example of Iran shows us the time of awakening has come. Fight against license and make sacrifices, to correct others and make our own revolution. . . . "

How was Ghannouchi going to "correct others" and "make" his "own revolution"? Fundamentalist students at the university of Tunis, Cooley reported in the same article, seized and held hostage the dean of the science faculty until he was freed by the police. After numerous similar acts of violence (hardly to be considered the expression of a democratic opposition), the case was referred to a Tunisian court, which, on Sept. 4, 1981, "sentenced 107 of the Moslem militants to prison terms from six months to 11 years. . . . The president and general secretary of the Fundamentalist Movement, Rached Ghannouchi and Abdelfattah Mourou, received 11- and 10- year sentences respectively." Both of them, however, were later pardoned by President Bourguiba.

Now once more some members of the movement are being prosecuted according to the provisions of the law, as evidence was gathered of their reliance on violence and their collusion with Iran. Although lately shaken by the impact of a series of external crises (threats, military intimidation, economic strangulation) and severe problems of recession, President Bourguiba has not followed other foreign leaders' more drastic solutions to the same challenge.

The Tunisian leadership is trying to cope with this difficult situation with calm and moderation. The implementation of a "structural adjustment program" has received the support of international financial institutions. Out of the four existing political parties, not a single one has been banned. No state of emergency has been declared, nor has a "police state" been installed in the country. The cases of Khemais Chamari (secretary general of the Tunisian Human Rights League), Habib Achour (former secretary general of the Labor Union) and that of the members of the illegal group The Socialist Progressive Rally, all of them freed recently, do demonstrate the flexibility and leniency of the regime and President Bourguiba's humane approach. Moreover, the opposition has been invited to participate in the Economic and Social Council, and in the creation of a constitutional council.

The different political tendencies, numerous publications from the opposition and free flow of international press are among the most visible manifestations of Tunisia's pluralistic society. This, we believe, is essential to our commitment to social justice and democracy -- a commitment we intend to keep in order to stimulate government action and help establish a check-and-balance system.

Tunisians, who have known for many centuries the real meaning of outside interference and who are now facing many difficult challenges, cannot afford to be caught again off-guard; and yet the principles of justice and democracy -- the seeds of which were so diligently planted through the years by Bourguiba -- are so deeply rooted in the country that it is hard to imagine a reversal in Tunisia's social and political openness.

-- Habib Ben Yahia The writer is Tunisia's ambassador to the United States.