Can Tunisia keep radical neighbors at bay?. Ability to fend off Libya, Algeria in post-Bourguiba era questioned

To the east is Libya's Col. Muammar Qaddafi, to the west is socialist Algeria. Sandwiched between two radical Arab states, Tunisian President Habib Bourguiba has so far managed to keep his neighbors at bay and independently forge a pro-Western policy. For Tunisia's former colonial power, France, as well as the United States, Tunisia's stability is of crucial importance. What Central America is to the US, North Africa is to France. And, as with the US, a primary French interest is to maintain a stable, friendly government in the region.

The most obvious external threat to Tunisian stability comes from Colonel Qaddafi. In recent weeks, Tunisia has sought to normalize relations with Libya and remove the threat of subversion from its eastern flank.

In 1985 Tunisia broke off diplomatic ties after Libya expelled 32,000 Tunisian workers and seized their assets. Libya also violated Tunisian airspace, and several letter-bombs in Tunis were attributed to Libyan agents.

Tunisia has lost an estimated $200 million in revenues it would have made from free-spending Libyan tourists and from worker's remittances in the past two years. The Libyans have now agreed to Tunisia's conditions for compensation. Several high-ranking Libyan officials have met recently with Mr. Bourguiba and his ministers to work out the details.

Even before 1985, the Tunisians were threatened by Libyan activities. In 1980, Libyan-backed Tunisian dissidents mounted an insurrection in the southern Tunisian town of Gafsa. The attack revealed serious weaknesses in Tunisian defense capabilities. The Tunisian military had to wait 36 hours until Morocco sent military transport planes to ferry troops to Gafsa. French aircraft overflew Tunisia to ward off Libyan intervention.

``After Gafsa, the government became conscious of the danger of Qaddafi and began modernizing the Army,'' says a former Tunisian security official.

Since then, the US government has supplied Tunisia with some $500 million in military assistance to counter Libyan threats. The Reagan administration has requested at least $40 million in military aid for Tunisia for fiscal 1988 to help deter Libya. After the break with Libya, the US and Tunisia formed a joint commission to discuss defense issues of common interest. The bulk of equipment in Tunisia's 40,000-man military is American.

Tunisia still has some major gaps in its defense system. In October 1985, Israeli warplanes bombed a Palestinian headquarters in a suburb of Tunis and flew back to Israel without being detected by Tunisian radar. The US's initial favorable reaction to the raid caused grave diplomatic and domestic problems for the Bourguiba government. Bourguiba said he felt personally betrayed by the US, and Tunisians marched on the US Embassy in protest.

The incident also forced the Tunisians to rethink their strategic doctrine. ``Until then the Tunisians assumed that they operated under a US umbrella,'' a Western diplomat says. ``Now they know potentially that the US will not necessarily intervene to save them from an attack.''

Though the US has sought to reassure Tunisia since then, the wound still smarts. ``That event appalled the Tunisians,'' says Prime Minister Rachid Sfar.

US-Tunisian relations were strained once again by the US raid against Libya last April. Though the Tunisian government is no friend of Qaddafi's, the Tunisian public resented having a superpower bomb a fellow-Arab state.

Bourguiba remains a moderate on Middle East issues, having often defied political trends in the Arab world. In 1965 he called on Arab states to recognize Israel, outraging then-Egyptian President Gamal Abdel Nasser and narrowly escaping several assassination attempts. When Arab states were caught up in a surge of pan-Arabism, Bourguiba saw it as an impractical policy.

As Bourguiba ages, both Washington and Paris have reportedly considered different transition scenarios, and the possibility of direct intervention should a violent succession struggle ensue.

Despite Qaddafi's belligerence, the possibility of a Libyan armed invasion seems slight, as that would justify direct Algerian and French action. A more likely scenario, Western analysts say, is Libyan support for internal destabilization.

It is the Algerian card that worries Tunisian politicians more. They fear Algeria would use Tunisian internal instability as a pretext to move in, and promote the idea of a ``Greater North Africa'' under Algerian control. Tunisians hope they will be able to decide themselves who should govern them in the future.

Third of four articles. The other two ran April 10 and 13.