In ways undreamed of by its promoters, President Carter's trip abroad announces the relatively safe state of the world. He is not, as his critics aver, journeying through an impossibly disparate range of countries.

On the contrary, there is a distinct logic to the President's tour. All the places he is visiting provide notable examples of international tensions on the way to being eased or localized.

India, the most distant point on the Journey, argues the case with special force. The transition from rule by Indira Gandhi and the Congress Party to rule by a loose coalition under Morarji Desai was a change fraught with danger of upheaval. The more so as similarly dramatic alterations in domestic politics occurred in the neighboring states of Pakistan, Bangladesh and Sri Lanka.

But the superpowers have long since ceased to contend in the subcontinent. Tensions once international in scope have been localized. Domestic politics have become domestic.

Carter's visit - no matter how much sympathy he shows for Desai and Indian democracy - cannot significantly affect the outlook for India. Probably the only immediate consequence of his trip will be a more jumpy attitude toward Washington on the part of the smaller states that have to live next to India.

Two major oil-exporting countries - Saudi Arabia and Iran - constitute a second, separate phase of the trip. Once highly important, they have lost weight in the world with the development of an oil glut likely to last until 1980. As monarchs vulnerable to popular unrest, moreover, the Shah of iran and king Khalid of Saudi Arabia need American support in a big way.

So this is the season for an arm's-length relationship emphasizing straight talk about international responsibility. The need is to make clear to the two monarchs that there will be very serious consequences if they play fast and loose with oil prices and supply. Indeed, it would not come amiss to revive at this time - both for dealing with the oil-exporting countries and for putting a little wholesome fear into the big companies - the idea associated with Morris Adelman, a professor at MIT, for a U.S. government role in the purchase of all foreign oil by American interests.

Unfortunately, that kind of talk does not take place at the summit among heads of government. Carter says tat in Saudi Arabia and Iran he is going "to let their people and those leaders know that I care about our friendship with them and vice versa." In other words, he will once again have no influence in a favorable situation.

Finally, there are three European stops: Poland, France and the NATO and European Community headquarters in Belgium. Relations with the Communist world are central to all three.

In Poland the President will express this country's continuing interest in the slow evolution of Eastern Europe away from total control by Moscow. That is happening anyway, as indicated by the praise lavished on the Warsaw regime by Stefan Cardinal Wyszynski in his Christmas Day message. So the President's visit is nice - but not necessary.

About the same is true for European defense and economic unity. In Brussels, Carter can at best promote a longterm change that is already moving - chiefly under its own steam.

In France, the President comes to grips with what once looked like the front end of the Eurocommunism threat - the possibility of Communist entry into government through a left-wing coalition apt to be victorious in the parliamentary elections this March. But the coalition has been badly damaged by infighting between the Socialists and Communists. Whatever Carter could have done to help the center under President Valery Giscard d'Estaing - which was always problematical - is now further diminished.

The purpose of Carter's trip, in these conditions, is not in doubt. After a poor season at home, he wants to associate with some winners. I hope the tactic works, but my sense is that Carter's domestic troubles are too deep - too much bound up with baffling conditions peculiar to this country - to be cured by a foreign tour.

But whether the tactic works or not, the trip should teach another lesson. It is the lesson that many international problems are now righting themselves. Satesmanship, accordingly, ought to be modest in tone and goal. The right image is George Kennan's image of "gardening." It is matter, as Earl Ravenal writes, "of following the natural contours of situations."