Paris — French President Francois Mitterrand is facing a rising chorus of questions about France's role in international affairs. During Mr. Mitterrand's first three years in office, he earned a reputation as a skillful statesman and France was the most active and visible Western country on the world stage after the United States. Doubts about France's ability to continue playing such a major role arose with last month's botched withdrawal from Chad and the eruption of violence in the far-off Pacific colony of New Caledonia.
Switching foreign ministers and giving a rare television interview devoted entirely to foreign policy have not muted the critical voices.
''Our credibility is at stake,'' says Philippe Moreau Defarges of the French Institute for Foreign Relations. ''The very independence of French foreign policy has become hypothetical.''
In the present mood, it is easy to forget Mitterrand's very real achievements. After years of squabbling, he restored France's good standing in the Western alliance by loud support of the deployment in Europe of US cruise and Pershing II missiles. American diplomats count France among the surest of the allies.
In Europe, too, the French President has played a constructive role. His good relations with West Germany and his successful presidency of the European Community during the first six months of the year make France central to continental cooperation.
''With considerable ability,'' writes A. W. Porte in Foreign Affairs magazine , Mitterrand has adopted ''policies which link France's permanent interests with reasonable effectiveness to an international environment over which he has, by his admission, only limited control.''
All of a sudden, though, Mitterrand seems to have lost that sure touch. In the past few months, the French President has traveled to Syria and received Israeli Prime Minister Shimon Peres and Jordan's King Hussein. Apparently with no results.
In Africa, the embarrassment has been much greater. Having his foreign minister declare Libyan troops to have withdrawn when they had not made him look foolish. Meeting Libyan leader Muammar Qaddafi in Crete at the same time provoked anger at home and from his African allies.
Then violence exploded in New Caledonia in the South Pacific. Mitterrand remained silent. The farms of European settlers there were burned - evoking memories of the French tragedies in Vietnam and Algeria - and the police did not intervene.
The carefully nurtured national consensus on foreign policy was shattered. For the first time, the opposition criticized Mitterrand on foreign policy.
A poll showed that only 28 percent of those questioned were satisfied with the President's statesmanship.
In response, Foreign Minister Claude Cheysson, who was held responsible for the Chad debacle, was replaced by Roland Dumas. But this was far from sufficient. A close personal friend, Mr. Dumas POLICY11POLICY9
is identified with the President - and indeed, since General de Gaulle's time , French foreign policy has been run primarily by the president. The country's prestige is tied to the president's prestige.
So Mitterrand made a rare TV appearance. For an hour, he defended his actions.
The TV lecture received mixed reviews, with critics lining up along party lines. The consensus among commentators is that - to truly restore his credibility - Mitterrand must not set his goals too high.
In the past, he succeeded by minimizing his risks. Early in his term, for example, he collided with Washington in an attempt to launch a peace initiative with Central America. Without much fuss, the initiative soon was dropped. Officials here explained it was not worth a spat with Washington over an area not vital to France and where France has no real leverage.
Present French policy in the Middle East must have similarly low goals. While he will talk to Syrians and Israelis, Mitterrand himself admitted that France cannot fill the role of primary peace broker in the region. Only America can. But the President hopes to convince the public that France's ability to talk to both sides makes it a useful peace partner alongside the Americans.
In Africa, Mitterrand insists France can play an even greater role. Paris provides most of the aid, trade, and military security for the French-speaking part of the continent. In turn, the former colonies remain the last place in the world where French influence predominates.
The Chad crisis has threatened that influence. It has undermined the confidence in the French security guarantee as well as raising further doubts that the French, hurt by a weakened economy, can continue providing aid and trade advantages.
But the French-speaking Africans have no substitute for the French option. Virulently anticommunist for the most part, they are not about to turn to Moscow. And despite African overtures, the United States has told the French that it does not plan to compete for influence in the region.
''If we play things right, we can still play a big role in Africa,'' says Mr. Moreau Defarges. Sure enough, African complaints have subsided in the past few days. Even normally belligerent Chadian leader, Hissein Habre, stated publicly after meeting Mitterrand, ''Our views are not totally divergent.''
Mitterrand's policies remain more problematic in two other areas, East-West relations and New Caledonia.
With Washington moving toward talks with Moscow, Mitterrand now feels the time is ripe for reheating his own connection with the Kremlin. Konstantin Chernenko is scheduled to visit Paris next year. Such a visit could once again raise expectations - and if nothing comes of it, deceptions.
''Any rapprochement with the East,'' warns L'Express magazine's foreign policy analyst Alain Besancon, ''could be compromising.''
New Caledonia could cause even more dissension. Already, the island's communal battle has spilled over to French politics. Mr. Besancon warns that a quick move to grant independence would split New Caledonia through its heart.
Of course, many other problems also could emerge. Libya's Colonel Qaddafi could move south, forcing French troops to fight a war in Chad's desert. French arms deliveries to Iraq could result in an outburst of terrorism. And so on.
''The difficulties are clear,'' concludes Le Monde editor Andre Laurens. ''There are all sorts of contradictions when a middle-level power tries to play its own role in the world.''