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.