In Washington the idea behind a special presidential commission is to take a controversial issue out of the political arena. This was the week when the idea did not entirely work for Central America.
President Reagan's special commission on Central America released its report amid a vivid controversy over how much more aid, and under what conditions, the United States will continue to give to a government in El Salvador which is unable or unwilling to convict and punish the right-wing murderers of some 30, 000 of its own people and a handful of US citizens, too.
It was also the week when President Reagan formally and publicly joined his three latest predecessors (Presidents Nixon, Ford, and Carter) in embracing mainland China as friend and trading partner. He had avoided doing that during his first two years in office.
And, during the past week, arrangements which would permit withdrawal of the US Marines from Lebanon without embarrassment to the President continued to elude his emissaries.
There will be continued US aid both to the official government of El Salvador and to the right-wing rebels trying to bring down the government of Nicaragua. Henry Kissinger, who headed the special commission, was able to obtain a consensus on those two points.
But he obtained that amount of agreement for existing Reagan policies only at the price of writing into the report a conditional clause. The government of El Salvador must do better than it has yet been able to do in curbing the notorious ''death squads'' and punishing the murderers of US citizens. So far three US nuns, one Roman Catholic lay sister, two US labor representatives working with the AFL-CIO, and one US Army officer have been killed in El Salvador without the culprits having been convicted and punished.
At this writing the White House is wrestling with the question of whether the President will accept conditions on further US aid to El Salvador. The aid has already been promised. There is anxiety that unless aid is quickly increased, regardless of what happens to the ''death squads,'' the armed forces of the regime could lose the war.
The civil war in El Salvador has been going poorly of late for the forces of the government. Even its best US-trained units have failed to stand up successfully to recent rebel forays. Morale among all units is said to be low. Rebels now exercise effective control over some substantial segments of the country.
Dr. Kissinger could get approval for more aid because the Democrats on the bipartisan commission did not want to find themselves accused of failing to support the anticommunist cause in Central America. But the matter of the still unpunished murders of US citizens rankles.
The murder of the three nuns and a lay sister happened in December 1980 after Mr. Reagan's election as President, but before his inauguration. There was an overtone in the deed of assuming that with Mr. Reagan coming to the White House the right-wing elements could get away with anything.
Political murders have continued to be endemic in El Salvador ever since. The unofficial estimate of the number killed by the right-wing ''death squads'' now stands at around 30,000 persons during the last five years.
Previous presidential commissions took the issues of social security and the MX missile out of the US political arena for 1984. A bipartisan consensus was achieved on both subjects. Presidential candidates now practicing their routines on the campaign trail avoid those two subjects which otherwise could have been the source of heated debate.
Dr. Kissinger has partly defused Central America as an election-year issue, but not entirely. Many Democrats have agreed that the US should continue to spend money to resist a communist success in El Salvador and to sustain the anticommunist rebels in Nicaragua.
The report favors a five-year military and economic aid program that would dramatically increase US assistance for Central America. It calls for some $8 billion in economic assistance alone. But many Democrats will not condone by inaction the record of the ''death squads.''
It took two years to convert Mr. Reagan to the idea that the US could associate in world affairs with the present government of mainland China. Relations with Peking were opened by President Nixon in early 1972. They were cultivated by Presidents Ford and Carter. But they were put on ice when Mr. Reagan took office in January 1981, and remained there through 1982.
Mr. Reagan's conversion to the acceptance of association with the regime in Peking dates from a trip there in February of last year by US Secretary of State George Shultz. Ever since there has been quiet progress, mostly in trade matters. This included a contract for American Motors to build four-wheel vehicles in China, and for oil drilling rights off China's coast by US companies.
Further agreements are being negotiated, including one providing for US technical help in nuclear energy. President Reagan welcomed Chinese Prime Minister Zhao Ziyang at the White House with a declaration that there is ''growing trust and cooperation'' between the US and China.
Prime Minister Zhao responded by reminding Mr. Reagan that China regards the sale of modern US weapons to Taiwan as interference in the internal affairs of China.
Mr. Zhao came to Washington not as a supplicant but almost as an act of condescension. There continues to be hope in White House back rooms that the recalcitrant Druze and Shiite communities in Lebanon will come to terms with the official government headed by President Amin Gemayel. This would permit the withdrawal of the US Marines without embarrassment or the appearance of retreating under fire. That in turn would defuse another potential election year issue for Mr. Reagan.
The campaign gets under way officially with the first primary election in New Hampshire on Feb. 28.