FRENCH PRESIDENT Francois Mitterrand was the last leader to arrive at the recent summit conference in Williamsburg. While Mitterrand descended from his horse-drawn carriage, President Reagan waited at the entrance of the governor's colonial house. As the two heads of state shook hands, the cameras captured more than just the encounter of two important leaders. They also showed the meeting of representatives of two diametrically opposed solutions to the world's economic recession. So far, neither solution has worked. And, as the summit conference highlighted, the future holds but slim prospects for either.

Reagan has adopted what might be called a "pre- 1930s" remedy for the recession. Decreased government spending, lower taxes and free trade are his tenets. Inflation is down to 6.2 percent, but the price, in terms of unemployment and creativity, may have been too high. During his first year in office, Mitterrand tried the "post-1930s" approach. Massive government spending successfully held unemployment in check, but produced soaring inflation and a feeble franc. Mitterrand has since adopted an austerity program to avert catastrophe. The five other nations present at the conference--West Germany, Italy, Canada, Britain and Japan--fall between these extremes, yet none but Japan has avoided economic dislocation. And 22 million people are unemployed in the summit countries.

Cooperation between the industrial nations is essential to promote recovery. Yet, as the Williamsburg summit showed, that cooperation is simply not forthcoming, and therein lies the greatest danger to the industrialized world. The Europeans believe that high American interest rates and the unstable monetary system that these rates have supposedly engendered are at the root of the economic mess. The Reagan Administration, though, is convinced recovery in this country will suffice to allow the United States to "pull" its European partners out of the recession.

But more active economic coordination on the part of the industrial democracies will necessitate more long-term planning. At last year's Versailles summit, Mitterrand made an eloquent plea for loosely planned economics emphasizing high technology--in essence, the Japanese model. The French president claimed that the Third World could serve as an ideal market for the new industries, which would further development as well. Hence the West and the developing world could find a common solution to their fundamentally different problems. Mitterrand's call went unnoticed, yet it has become all the more urgent with the passage of time.

In the West, ideology stands as the principal stumbling block to the adoption of loosely planned economics. For Reagan, Britain's Margaret Thatcher, and to a lesser extent West Germany's new chancellor Helmut Kohl, such a policy stinks of socialism. Yet the "isms" of yesterday seem particularly irrelevant today. Socialism in the East is bankrupt: people are not adequately fed, housed or provided for, Western capitalism seems equally out of breath, insensitive to the cost in human terms of successive crises. The future lies in a break from the constraints of ideology and the embrace of a new, non-sectarian system.

LOGICALLY ENOUGH, the ideological framework that hinders economic recovery also perverts international political relations. The inability of the United States to see the world through anything other than an East-West prism is not a new factor, but has become particularly dangerous given the upheavals in Central America. The United States is presently engaged to some extent in El Salvador and Nicaragua. In both countries, the Administration is pursuing ideologically rigid policies that seem destined to fail.

The original sin in El Salvador was viewing the guerrillas solely as Soviet surrogates. Conflict in El Salvador resulted from economic, political and social inequities, not the long arm of the alleged worldwide communist revolution. But the Administration never negotiated seriously for a settlement. Last year's supposedly "democratic" elections backfired when an extreme right coalition took power. And they were a scheme to begin with because the guerrilla--afraid they would be murdered by the military--did not participate.

Now, of course, the situation in El Salvador has become as polarized that many of the guerrillas are in the Soviet camp and it may be too late for a peaceful settlement. Yet continued civil war--and that, clearly, is the logical result of Reagan's policy, for side, short of outright intervention by the United States, can win--means more senseless deaths. A last--ditch attempt at a settlement is imperative if we are to prevent the Vietnam analogy from becoming more than just effective rhetoric. But as the recent dismissals of Undersecretary of State for Central American Thomas O. Endears and U.S. ambassador to El Salvador Dean Hinton show, such a change in policy is not in the cards. Both Endears and Hinton advocated a double-tracked plan of continued military aid to the Salvadoran government and negotiations with the guerrillas--better, certainly, than no talk at all. Now guns will do the only talking for American diplomacy in El Salvador.

In Nicaragua, the Administration is concerned that the Sandinista regime is a Soviet lackey and has been supplying arms to the Salvadoran leftists. On both counts, the Administration is probably not far from the mark. Tragically, though, American policy may have been what pushed the Sandinistas into the Soviet camp. When he came to power, Reagan cut off all aid to Nicaragua, which was forced to turn elsewhere--i.e. to the Soviet Union--for economic assistance. Then word began to leak out that the Administration had okayed CIA plans to overthrow the fledgling regime. The Sandinistas initiated a significant military build-up and restricted human rights in Nicaragua. A vicious circle evolved.

The United States' troubles in Central America stem from the larger question of how to deal to with the Soviet Union. The Administration's policy is reminiscent of nothing so much as the containment theory of the 1950s. Then, as now, the Soviets had to be stopped in every area they were perceived to be on the move. And the problem now, as then, is one of ridiculously polarized perception. For as the case of Central America shows, the USSR is simply not the root of all the world's problems. The USSR seems to act more as a typical superpower best on securing its borders and establishing allies than as a fanatical breeder of revolution. This reality must be taken into account by American foreign policy makers.

EVEN MORE IMPORTANT is the realization that the one thing the United States and the Soviet Union have in common--the threat of nuclear annihilation--far outweighs all their differences. Yet progress on arms reduction talks has been minimal. The deployment by the Soviet Union of $$-20s has not helped the cause of arms control, but neither has the Reagan Administration's implicit rejection of deterrence. The Administration believes that purity, not sufficiency, must dictate our defense policy. But purity is in the eyes of the beholder and therefore constitutes a dangerous basis on which to build a strategy.

A brief tour of the world, then, does little to inspire optimism. And these broad problems overshadow equally pernicious dilemmas such as human rights, hunger and poverty. Yet two underlying facts, if properly understood and acted upon, could constitute, the hope for tomorrow. The world is increasingly interdependent, a bad thing if there is little cooperation among nations, a good thing if allies--and adversaries--can manage to get along. The key to cooperation lies in the rejection of the old sectarian world and the acceptance of the idea that our common problems have superseded ideology. Espousal of these new facts of life has been tortuously slow in coming. But with each passing day, it is clear that there are no alternatives.