WHEN SOMEONE in the U.S. government tells us at this newspaper that certain material we are considering publishing would, by its publication, adversely affect the national security, we take the admonition seriously. We listen and we decide what to do. The Washington Post has in fact declined to print material in this category over the years on some occasions. The story currently in the news that has caused so much consternation -- our Tuesday account of the government's plan to launch a new military intelligence satellite on the next flight of the space shuttle -- was such a case. Certain material which the Pentagon would not want released was in fact withheld by our reporter, although we were not among those called and asked by Secretary Weinberger not to print the story.

The general outline of the story and many of its specifics had been floating around the governmental and journalistic worlds for months. They didn't get there from nowhere: They had been disclosed by military and civilian government sources. Readers of American publications -- including this country's adversaries, of course -- had long since been able to read virtually all of the material that was to appear in the Washington Post story. They had been able to read it elsewhere in the open -- i.e., unclassified -- literature. Some of this material had been printed in other publications, such as Aviation Week and Space Technology, and broadcast on CBS. Some came from the Reagan administration's public testimony on Capitol Hill.

The Washington Post does not quarrel with Secretary Weinberger's insistence on fulfilling his obligation to protect the national security and also to protect those defense secrets that are essential to it. We do dispute his characterization of our story as representing an irresponsible security breach. Elsewhere in this newspaper today you will read citations from the public literature on which our Tuesday report was based. If there were security breaches, we believe, they occurred well before this particular account was printed.

We reserve the right, as all self-respecting journals do, to challenge the government's decisions as to what material is and is not suitable to print. And we have no doubt that we will be in many disputes with many administrations on this score in the future -- as will our journalistic colleagues. But the intelligence satellite story was not one in which we were setting out to break new ground or in which we carelessly chose to violate security strictures. We believed we were printing a newsworthy story on a subject that had been getting ever more attention this week and that we were staying within the bounds of responsible, informative journalism.