Not all Reagan's troubles are made in Moscow

World affairs focused over the past week on a central question. Will American President Ronald Reagan get his big arms budget through Congress more or less intact and his new weapons program lined up and working before he has to sit down and bargain with the Soviets over arms limitations and controls?

In Washington Mr. Reagan took to the airwaves with a major selling job for the arms budget. His secretary of defense, Caspar Weinberger, was in Portugal trying to persuade other NATO defense ministers of the importance of getting the budget first, then talking to the Soviets.

The President's special commission on what kind of MX to build was nearly ready to report. The Pentagon claimed that the new Pershing II missile, due to begin deployment in Europe in December, has passed its trial tests.

Production and deployment are in order. New cruise missiles are also said to be ready for deployment.

But another wave of antiweapons demonstrations was being prepared in Europe. Will the West European NATO governments be able to go ahead with the deployment of American weapons on their land without progress toward arms limitations and controls?

It was a picture of maneuvers in which Moscow and Washington are concentrating on getting into the best possible bargaining position before the inevitable day when they face each other in a major round of negotiations.

For Moscow the best possible situation would be to have the European members of NATO refuse to permit deployment of Pershing II and cruise missiles in Europe until a bargain has first been struck, and to have Congress cut the arms budget back substantially.

For the President the ideal would be for Congress to approve the entire budget, the Europeans to accept the new missiles without condition, and the MX to be installed. Then he could go to the bargaining table with a handful of trumps.

Much turns on how effective his March 23 television speech will prove to be in influencing American public opinion and the Congress to support the full arms budget and the full deployment program.

Much depends also on whether the Reagan team in Washington can clear up some of the muddles which have been delaying the program. For example, the MX is still held up over the fact that the two original proposals for its method of deployment (the ''race track'' plan during the Carter administration and the ''dense pack'' plan proposed by the Reagan administration) ran into overwhelming political opposition. No state wanted the ''race track'' within its borders. The ''dense pack'' concept met incredulity. In Congress it did not seem to make sense.

More delay has been caused by the dismissal of Eugene Rostow as director of the Arms Control and Disarmament Agency followed by trouble over his proposed successor. The President named Kenneth Adelman, whose limited experience and performance at Senate hearings raised doubts about his qualifications for the post.

Chief arms control negotiator Edward Rowny was also in political trouble over a memorandum containing what some senators called a ''hit list'' of people he allegedly did not want on or near his negotiating team. One senator, Gary Hart, named on the list happens to be a Democratic candidate for the presidency.

It was not easy for the President's staff to come up with a new US negotiating position without a sitting director of the arms control agency and with a chief negotiator in political trouble.

Fumbling inside the administration has been part of the cause of the delay in getting the arms program in place and a bargaining position worked out. Not all Mr. Reagan's troubles are made in Moscow.

Other events of note in the world during the past week included the return of a Chinese delegation to Peking after three weeks of talks in Moscow. The Soviet press tried to make it sound as though progress had been made toward ''normalization'' of relations between the Soviet Union and China. But the Chinese failed to confirm the Soviet version.

The Soviets had sought the talks. The Chinese agreed to go to Moscow and listen. They listened for three weeks, and then went away without doing any talking in public, and apparently little even in private.

There are reports of some decline in friction between Soviet and Ch)n%se troops along the border. A trade agreement was signed which is supposed to increase the volume of Sino-Soviet trade. But the Soviets refused to consider Chinese demands for withdrawal of Soviet troops from Afghanistan and an end to Soviet support for Vietnam's invasion of Kam-puchea (Cambodia).

Also noteworthy during the week was a claim by counterrevolutionary Nicaraguan forces to have succeeded in establishing themselves inside Nicaragua in an area fairly close to the capital. Previously the right-wing Nicaraguan forces had been operating in Honduras along the border, making frontier raids into their home country. Now they claim to be established inside.

Reporters who investigated the claim failed to find rebels in control of any city.Ebhhhroever, the rebels enjoy unofficial although well-documented US aid. With an ample supply of funds and arms from the CIA, it is possiqvyh zx h zy hzx- -/O-dropped into the mountains and are busy setting up an operating base. The Nicaraguan rebels seem to be modeling their campaign on the slow one which Fidel Castro used during his original bid for power, rather than on the disastrous Bay of Pigs affair mounted by the Cuban right-wing rebels against Castro.