On the great-power front of world affairs we now have an unusual and interesting new situation.
In Washington, President Reagan is trying to outflank the Soviets where in the past they have been strongest - in weapons - while in Moscow the new head man, Yuri Andropov, has committed himself to trying to outflank the Americans where over the past decade they have been strongest - in the diplomacy of alliances and associations.
The events of the second week in the reign of Mr. Andropov in Moscow have largely served to confirm the indications of the first week. He is out to woo the Chinese and relieve the anxieties of his neighbors to the south and west. World chancelleries expect a propaganda peace offensive, with Western Europe as a major target.
At the same time, President Reagan unveiled in Washington his chosen mode for deployment of the new MX il6l,0,9l,4p6intercontinental ballistic missile. A hundred of them are to be placed in a 20-square-mile strip in Wyoming.
In theory the new MX, plus the Pershing II and cruise missiles which are scheduled to start deployment in Western Europe during the coming year, will wipe out the advantages in nuclear weaponry which the President claims the Soviets now enjoy. This in turn is supposed to bring the Soviets to the bargaining table. The end result is supposed to be a restored equilibrium in nuclear weaponry between the two superpowers.
In effect, the picture which now emerges exposes a reversal of grand strategy by both superpowers.
Over the past decade Moscow has so frightened and alienated others by its pursuit and use of military power that it has virtually isolated itself diplomatically. Its most loyal allies, Vietnam and Cuba, have been purchased at exorbitant cost. Today Moscow has few, if any, unpurchased willing friends.
The United States over this same 10 years has been consolidating associations and friendships while allowing the Soviets to catch up in military power.
The result has been containment of the Soviets by the combination of the NATO alliance on one flank and an improving association with China on the other. But the ability of the US to use military power itself, as it did in the Cuban missile crisis, has been in turn contained by the rising military strength of the Soviets.
Ever since Richard Nixon went to China in 1972 there has been a precarious balance between rising Soviet military power and a superior American system of associations, friendships, and alliances. Mr. Nixon deliberately substituted diplomacy for raw power. After going to China he authorized a decline of 1 million men in the overall military manpower of the US - down from 3 to 2 million. Weapons procurement was trimmed back proportionately to the decline in manpower. And he promulgated the ''Nixon doctrine'' of helping friendly nations to help themselves, rather than be totally reliant on direct US power.
A careful reading of the text of the first speech which Mr. Andropov made on Nov. 22 to the Central Committee of the Communist Party of the Soviet Union (the equivalent of the President's annual State of the Union speech in Washington) shows that Mr. Andropov is just as unhappy about Moscow's diplomatic isolation as President Reagan has been about the Soviets' military posture. Each envies the other. And each, obviously, is out to gain where it has been weaker.
Above all, Mr. Andropov wants to break up the association between the US and China which Richard Nixon initiated and which his successors, Gerald Ford and Jimmy Carter, nourished. Here he has a reasonable chance for a diplomatic breakthrough. President Reagan has obviously never appreciated the fact that the association with China literally was worth a million soldiers to the US because it tied up something approaching that number of Soviet troops on the Chinese frontier. Hence the China connection was left untended during the first two Reagan years, or rather it was weakened by the Reagan warmth toward Taiwan.
China was waiting to be wooed by anyone from Moscow with enough imagination to realize the opportunity. Mr. Andropov has realized the opportunity.
How far can he get in wooing Western Europe?
That is less clear, although the rift between Mr. Reagan and his NATO allies over the pipeline affair has certainly left some bruised feelings in Europe. Mr. Reagan will have to try harder if he wants to keep the NATO allies vigorously on his side.
Mr. Andropov's main difficulty in pursuing his diplomatic offensive will continue to lie in the relative economic weakness in the communist system. Trade is the handmaiden of diplomacy. Nations tend to make political friends out of their best trading partners. Moscow has so little with which to trade, either in consumer goods or high technology machinery.
Mr. Andropov recognized this weakness in his speech. At the very beginning, before he talked about world affairs, he said that Soviet labor productivity grows at a rate that ''cannot satisfy us.'' (Actually, it is probably declining - not growing at all.) Also he spoke of a ''need to extend the independence of amalgamations, enterprises, and collective and state farms.'' He proposed to ''take account of the experience of fraternal countries.'' This last is an obvious reference to the more productive economies of Hungary and East Germany.
Economic health is the foundation both of successful diplomacy and of strong military power. Mr. Andropov obviously knows that he must revive the Soviet economy. But he has a formidable problem. His is a one party state. The party is largely made up from the bureaucracy. The bureaucracy thrives on centralized economic planning. The more inefficient the central planning system, the more jobs for the party faithful.
A pilot project in breaking up centralized economic management appears to be tentatively under way next door in Poland. General Wojciech Jaruzelski is reportedly trying to decentralize the Polish economy and revive some elements of individual enterprise as has been done successfully in Hungary, and to a degree, East Germany. But he has run into stiff resistance from inside the Communist Party. He is threatening the party hacks with loss of their cushy jobs.
It is easier to cut the government payroll and get rid of time servers under a multiparty system than in a one-party state.
Mr. Reagan is also running into obstacles in his effort to build a superior American military power. The mere cost at a time when unemployment is high and budget deficits are rising arouses automatic resistance in Congress. Besides, the case for the MX is a shaky one. Many an expert says that there is nothing an MX can do that can't be done just as well, and for less money, by a cruise missile or, later this decade, by new Trident II missiles aboard submarines.
In the end Mr. Reagan and Mr. Andropov may each have to go on envying each other and trying with limited success to gain what the other has. Moscow's main strength is military. America's main strength is economic and diplomatic.