A triangular great-power struggle could be shaping up over the continued presence of 12,000 Libyan troups in the sub-Saharan African state of Chad. The three great powers involved are the United States, the Soviet Union, and France.
Given the newly developing association between the Soviet Union and Libyan leader Muammar Qaddafi, it can be assumed that Moscow is on the side of keeping the Libyan forces in Chad. Colonel Qaddafi said publicly at the beginning of the month that they had to stay because Chad was "a strategic ramp" into Libya from the outside.
Both the US and France want the Libyan troops out, but there is a risk that the two Western powers will find themselves at odds about the best way to secure the troops' withdrawal.
France, under its new Socialist President, Francois Mitterrand, is exploring the path of diplomacy and is offering Chad President Goukouni Woddei -- who initially invited the Libyans -- limited French economic help to lessen his dependence on Colonel Qaddafi.
For the US, with the Reagan administration in its present tough anti-Qaddafi and anti-Soviet mood, the temptation is to choose instead confrontation and support for open, armed resistance to any anti-Libyan and anti-Goukouni forces in Chad.
The Libyan troops in Chad are more than a local threat: From the outset they have had the potential of becoming a pawn in the superpower struggle between the US and the USSR. Colonel Qaddafi has been drawing ever closer to Moscow, and his troops could therefore become Soviet proxies in Chad or even farther afield in Africa.
To the east the troops threaten the pro-Western governments in Egypt and Sudan.
To the south and west, backed by Colonel Qaddafi's oil wells and proselytizing revolutionary brand of Islam, they threaten to destabilize all the sub-Saharan states with Muslim populations or minorities -- from Nigeria, the populous giant of black Africa, to the sparsely peopled, impoverished smaller French-speaking states still largely dependent on France for their survival.
Against this background should be seen:
* The impending visit to Washington Sept. 25-29 of the French Cabinet minister most deeply involved in applying French policy in Chad, Jean-Pierre Cot.
* The Sept. 17 visit to Paris of Chad President Goukouni for consultations with President Mitterrand and Mr. Cot.
* Mr Goukouni's visit to Libya at the beginning of the month to participate in celebrations marking the anniversary of Colonel Qaddafi's coming to power in 1969.
* The upsurge of incidents on the Chad-Sudan border, reportedly involving Libyan troops, the anti-Goukouni forces of former Chad Prime Minister Hissein Habre, and the Sudan defense forces.
The Libyan troops were invited into Chad Sudan border, reportedly involving Libyan troops, the anti-Goukouni forces of former Chad Prime Minister Hissein Habre, and the Sudan defense forces.
The Libyan troops were invited into Chad last year by President Goukouni to help him deal a knockout blow to Mr. Habre's forces. A long period of civil war had ended with the two men locked in a stalemate, which the arrival of Libyan troops resolved in Mr. Goukouni's favor. Mr. Habre and the remnant of his forces took refuge close to the Sudan border near Abeche.
One of the early effects of the penetration of Libyan troops deep into Africa -- an effect of considerable consequence but little noted outside the area -- has been a burying of the hatchet between France and Nigeria. For nearly two decades, each had seen the other as an obstacle to its ambitions in the region.
The Qaddafi threat has now brought France and Nigeria together in a rapprochement begun when Nigerian Foreign Minister Ishaya Audu visited Paris in January, before President Valery Giscard d'Estaing left office. It was advanced further in August -- after Mr. Mitterrand assumed the presidency -- when Mr. Cot visited Lagos. It can be assumed that one of his aims was to coordinate French and Nigerian policies toward Chad.
Between the two French-Nigerian meetings, the Organization of African Unity (OUA) at its June summit in Nairobi softened an earlier African stand on the Libyan presence in Chad. Instead of calling (as the Africans did originally) for immediate withdrawal of Libyan troops and their replacement by an inter-African force, the OAU June resolution left it to President Goukouni's discretion as to when Libya should be asked to pull out. The resolution preserved the concept of an inter-African force but set no date for its establishment.
While Mr Giscard d'Estaing was still president, Mr. Goukouni had started making signals to France to come to help bail hil out of the Libyan embrace. Presumably he felt able to do this because France had been Chad's patron until mid-1980. Mr. Giscard d'Estaing's response to the signals was stern: no French help before the Libyan troops are withdrawn from Chad.
The OAU resolution has given Giscard d'Estaing's successor an opening for a cautious French return to the diplomatic game in and over Chad. The French perception is that the empty French chair in the Chad game as profited France nothing. The French aim, under Mitterand, is to strengthen Mr. Goukouni's hand so that he feels strong enough to ask Colonel Qaddafi sooner rather than later to withdraw the Libyan troops.
With this diplomatic activity coming to the surface, it is perhaps no coincidence that the remnant of Mr. Habre's anti-Goukouni forces should feel that this is the time to call attention to themselves as a potential threat to Goukouni and his Libyan supporters. The recrudescence of hostilities by the Habre guerrillas is north and south of the road from Abeche in Chad across the frontier to El Geneina in Sudan.
Last week Sudan claimed that the Sudan defense forces and the Habre guerrillas had shot down a Libyan Italian-built bomber in the Abeche-El Geneina area. Sudan has also reported Libyan ground attacks on Sudanese villages. On Sept. 16, President Nimeiry of Sudan appealed to the UN Security Council "to take decisive measures" against these incursions.
Sudan's initiative would imply Sudanese support for Mr. Habre. It is suspected that Egypt -- which has a defense pace with Sudan and shares hostility toward Colonel Qaddafi -- may also be backing Habre.
Last week US Secretary of State Alexander Haig, speaking to the Senate Foreign Relations Committee, spoke of Sudan's getting US assistance because it was among "targets of Libyan expansionism." So an as-yet unanswered question is: Could the US be encouraging Sudan and Egypt to whatever they may be doing to egg Mr. Habre on