IF YOU WERE puzzled, as we were, by the administration's proposal last March to sell the government's weather satellites to private enterprise, you may find the circumstances surrounding the resignation this week of Deputy Secretary of Commerce Guy W. Fiske illuminating. Mr. Fiske was, in his own words, "an expediter" of the Commerce Department's deliberations on the proposal to sell the satellites. It was not a proposal that ever made much sense: even if you accepted the administration's projections--and they were rejected in a 1982 study by the Defense Department and the National Aeronautics and Space Administration--it was not clear that any public money would be saved, and less information would be available to farmers, businessmen and others who can make economically productive use of weather forecasts. Moreover, the deal proposed by the only interested buyer, Comsat, did not look attractive: land and weather satellites that cost the government $1.6 billion to launch would be sold to Comsat for some $300 million, and the government would guarantee that it would buy weather data from Comsat.

It's not hard to see why Congress wanted nothing to do with this deal, but it was harder to see why the administration endorsed it. Now it comes out that Mr. Fiske, at the same time he was expediting the matter, was also talking with Comsat officials who were looking for a new next president. Mr. Fiske says that the job talks never reached actual negotiations and that no connection was implied between the job and the proposal. But the timing, as related by Post reporter Philip J. Hilts, is suggestive. As late as October 1982 the administration maintained a longstanding decision not to sell the satellites. In November Mr. Fiske held the last of several job discussions with Comsat officials. At a Cabinet Council meeting that same fall, Commerce Secretary Malcolm Baldrige argued for and won approval of the policy to sell the satellites.

Now Mr. Fiske has resigned and has admitted that his November meeting was "a mistake." The Commerce Department's general counsel stated in an internal memorandum last month that Mr. Fiske violated department standards of conduct and created the appearance "of (a) using public office for private gain; (b) giving preferential treatment to the corporation; (c) losing complete independence or impartiality." The Justice Department is investigating to see if Mr. Fiske violated any criminal laws.

There is at least one lesson that ought to be drawn from this. An administration that believes that the public good is often best sought through maximization of private advantage needs to take special care to prevent the use of public office for private gain.