Paris — An international odd couple - Ronald Reagan and Francois Mitterrand - meet in Washington Wednesday to celebrate the unusual and unexpected friendship between conservative America and Socialist France.
The planned red-carpet welcome, complete with 21-gun salute and state banquet indicates Mr. Reagan's genuine appreciation for the French President's tough foreign policy. Mr. Mitterrand participated in the peacekeeping effort in Lebanon, checked Libyan ambitions in Chad, and firmly supported the deployment of new American missiles in Europe.
''All the fanfare for President Mitterrand reflects our deeply-felt good will ,'' says one American diplomat.
The relationship, to be sure, has its rocky spots. No French president, after all, can completely ignore Charles de Gaulle's legacy of proudly proclaiming independence from the United States.
The French openly disagree with Washington's Central American policy - specifically on El Salvador and Nicaragua. They oppose US efforts to keep the Soviets out of Mideast peacemaking. And, as the squabble over the Soviet pipeline contract shows, they will not accept American pressure to cut trade with Moscow.
''But these misunderstandings are normal,'' a top French diplomat says. ''In the issues outside of Europe, such as in the Middle East and Central America, we think Washington overemphasizes Soviet influence. Local causes are more important. On the big issue, though, the Atlantic Alliance, we see eye to eye.''
This means Mr. Mitterrand regards the Soviet threat in Europe as seriously as Reagan does - and unlike his predecessors, he has not been afraid to forcefully state his worries in public. In supporting deployment, for example, he declared, ''the missiles are in the East, the pacifists in West.''
Mitterrand's one-week coast-to-coast visit will highlight the positive agreement, ignoring the side irritants. No key agreements or policy initiatives will be made.
None are necessary, American and French diplomats agree.
''Why focus on small problems when our cooperation is what's really important?'' asks one adviser to Mitterrand.
Indeed, the alliance needs this French solidarity. During the l960s, the United States could count on Bonn to anchor the continent. But today West Germany is buffeted by pacifism and anxious to salvage the remains of detente.
France, meanwhile, has shed de Gaulle's scorn for the alliance, and at the same time, avoided the strains of divisive neutralism.
The transformation has been striking enough to make US diplomats here ponder in private whether France and West Germany have quietly reversed roles.
An intellectual shift mirrors this political transformation. Anti-Americanism , so popular a few years ago, is no longer fashionable.
Two Burger Kings sit proudly on the Champs Elysees. In a larger sense, too, intellectuals and artists who not long ago idolized the Soviet Union now celebrate American freedom and affluence.
The publication of Alexander Solzhenitsyn's ''Gulag Archipelago'' forced the French to think more carefully about human rights - and here America, despite its foibles, from McCarthyism to Vietnam, looks good. And the failure of the Soviet economy has made America's economic success more striking.
''There has been an intellectual revolution in the past couple of years,'' says respected author Francois de Closets. ''No one laughs at American capitalism and freedom any more. We realize that your system is more dynamic, and less class-bound, than our own.''
Historically speaking, this new French affinity for America is understandable. The Marquis de Lafayette fought alongside General Washington, after all, and without French help, the colonies might never have gained independence. One hundred years later, the French felt warmly enough toward the United States to present it with a special birthday present, the Statue of Liberty.
Anti-Americanism only set in after World War II. Much of the anger was due to General de Gaulle, who felt snubbed during the war by President Roosevelt and went out of his way to defy the US.
But the mood transcended the General. His strident independence captured the mood of a nation trying to find its role on the world stage after the devastating defeat in World War II. And at this time, the left looked East, not West, for inspiration. Today, the situation seems reversed. Officials here worry that the United States is beginning to scorn Europe.
Polls showing that Americans don't trust Europeans much, especially the French, sparked the fears.
And recent speeches by former Secretary of Defense James Schlesinger, former Secretary of State Henry Kissinger, and present Under Secretary of State Lawrence Eagleburger - all berating the Europeans for weak will, and suggesting that America should turn its focus of interest to Asia with its greater commercial possibilities - increased those concerns.
''The voters say 'No adventures,' so every election year America becomes isolationist,'' one Mitterrand adviser says.
''But it seems that the US has become less interested in Europe. No president , after all, has been elected from the East coast since Kennedy.''
In the long run, this trend may make the recent Franco-American warming insignificant. But at least this coming week, America will benefit as the strange partnership of Francois and Ronald continues to strengthen.