Responding to mutterings about the extravangances of the French court of Louis XV, one of his favorites, Madame de Pompadour, is supposed to have said, "apres nous le deluge." None of that for Ronald Reagan. In Paris, London, Bonn and Rome for the next 10 days, Ronald Reagan is going to be the deluge.

Extravagantly, in living color, he will be saturating the air waves, flooding onto television screens, engulfing viewers. With long and loving attention to detail, his White House cruise directors have set in motion what has to be the most concentrated and calculated international public relations blitz in the age of modern communications. That's not the cynics talking. That's how the White House has been presenting it, unabashedly, with ill-concealed pride and refreshing candor about its handiwork.

Candor, you could say, to a fault. If there is any danger in the Reagan deluge, it lies in the possibility of what you might call overflow. When you count up all of the "live" television opportunities along the way, you have to wonder whether, somewhere, there is not a European saturation point, when the hands of the handlers begin to show, the game gives the game away, and a certain skepticism (ever present in the European view of Americans) sets in.

I am not quarreling with the basic strategy of this "public diplomacy," as it was described by White House Communications Director David Gergen at a preview briefing for a handful of news people the other day. He is quite right in believing that "many in Europe obviously do not know the man well or understand him well."

That a large part of this misperception of Reagan, the hip-shooting cold warrior, is largely of his own making takes nothing away from the importance of the exertions to present Ronald Reagan, world statesman, with a balanced view of the problems of war and peace, a sure command of subject matter, a sensitivity for European concerns. As Gergen put it: "This (is) an excellent opportunity to bring the man, his leadership and his philosophy to the European public. We are treating the trip with recognition of how important that can be to our overall diplomatic efforts."

The importance of the opportunity is underscored by the relatively bloodless nature of the private diplomacy the president will be caught up in. Matters of considerable moment, some murky and others downright rancorous, will be dealt with at the business meetings of the economic summit of the seven industrial great powers at Versailles and of the soon-to-be (with the admission of Spain) 15 members of the North Atlantic Treaty Organization.

But as has become the custom in these gatherings, progress will be measured less by what is achieved than by what is forestalled--by the forswearing, before witnesses, of unilateral mischief-making in favor of multilateral muddling through. The United States will tone down its refusal, ever, to intervene in the money markets in support of the dollar. Solemn American assurances will be given that, yes, the high U.S. interest rates that are the bane of the European economies will be coming down.

Reagan, it is said, will come up at the NATO session in Bonn with a new proposal for negotiating a reduction of conventional forces on both sides of the line in Europe. "We are not going over there to pander to the peaceniks," says Gergen. "But we do want to talk about the need to reduce arms."

At the economic gathering in Versailles, there will be heavy emphasis on the perils of rampant protectionism and the need to ward it off by careful, collective preparation for international trade talks scheduled for November.

Based on all the advance billing, both summits promise to run pretty much true to form, which is a lot closer to group therapy--a chance to talk out potentially explosive and divisive issues--than to a negotiating, and still less to a decision-making, process.

Meantime, on camera, those Europeans with a keen interest in the American president will be enjoying a movable feast. By careful prearrangement, almost everything will be broadcast "live": a speech to the British Parliament, another at the Berlin Wall, another to the German Bundestag, another at the Vatican. Even a pre- trip appetizer, in the form of an interview with four European networks, was billed as "live"-- though it was aired several days later and its production was tightly controlled.

At last report, no freewheeling press conferences were planned--no opportunities for mishaps. For the most part, the president will be setting forth, in policy statements long in preparation, his broad views on "unity"--of shared values, of economic interests, of security concerns. It will be by far the most comprehensive statement of his foreign policy--no less valuable for being somewhat overdue.

And Gergen's right: if Reagan can build European public support for U.S. policies, his life with alliance leaders will be made a lot easier over time. How much easier, however, depends on how this TV serial, with its attendant evidence of calculation and contrivance, actually comes across--as "Ronald Reagan: The Making of a Statesman" or "Ronald Robot, the Programming of a President."