Now and then I feel slightly chagrined to be an American. I've felt that way in England, when a raucous outburst at the other end of a sedate railway car resolved itself into unmistakably American accents.
I've felt that way in El Salvador, when the breezy self-assurance of some American officials seemed hardly adequate to the complexities of the situation.
And I felt that way the other night after seeing ''The Right Stuff'' - that raucous, breezy, and ultimately trivial movie about the American space program in the 1950s and '60s.
I'm not embarrassed about the space program itself. Far from it. In those vigorous decades it seemed to capture, with its mixture of pragmatism and idealism, the essential character of the nation.
Henry Steele Commager put his finger on that character when, seven years before Sputnik was launched in 1957, he wrote that ''Progress was not, to (the 19th-century American), a philosophical idea but a commonplace of experience. . . . He planned ambitiously and was used to seeing even his most visionary plans surpassed; he came at last to believe that nothing was beyond his power and to be impatient with any success that was less than triumph.''
The space program was, in large part, that kind of success. It's difficult to imagine how the present age of global communications could have arisen without that pioneering effort.
No, what troubles me is the movie itself. Granted, it provides a historical overview of a period well worth remembering. Granted, it has moments of comedy, generally credible acting, and some convincing special effects. Yet it largely misses the mark for three reasons:
* First, it trivializes the space program. That program could hardly have been orchestrated by such a cornball assortment of incompetents as the film gives us. Among the caricatures: dense but devious politicians, silly bureaucrats, inane journalists, and haughty Germanic engineers more appropriate to ''Hogan's Heroes'' than to the subject at hand.
* Second, it trivializes the astronauts. The film portrays them as cardboard-cutouts from a Class C western, not as well-rounded characters caught in conflicting loyalties to family, nation, and individual aspiration. Although the movie approaches such themes, it constantly turns away from probing insight toward either the cheap bathroom laugh or the musical-visual spectacle popularized by ''Star Wars.''
* But primarily it trivializes the notion of heroism. It focuses on the mere fruits of heroism without providing any genuine study of what made those men heroes - beyond their ability to endure the exhaustive workouts demanded by the medical teams. Were these men really heroes? Or were they little more than articulate chimpanzees, laboratory specimens testing the effects of space on living organisms? The film refuses to say.
Well, so what? Hollywood has once more trivialized heroism: Why the concern?
The concern arises because, like it or not, ''The Right Stuff'' is an important film. That is partly because of its political timeliness. Providing a sympathetic portrait of then-astronaut, now-presidential-aspirant John Glenn, its impact on the 1984 campaign will be debated by future historians. Not surprisingly, the crowds are already flocking in.
Yet many of those who see it, I think, have something more than politics on their minds. Outside the theaters, on those other screens in their living rooms , they are watching events in Lebanon and Grenada. They see American troops in action; they hear talk about heroism. And they need answers to some deep questions. Can a space program or a high-tech military operation - where individual decisionmaking is so clearly subordinated to collective action - foster heroism? Do Hollywood's gritty, self-assured, swaggering figures - devoid as they are of the genuine nobility, sacrifice, and dedication that comprise human greatness - really fill the bill?
The storyline of ''The Right Stuff'' quite properly answers ''No.'' But the film's symbols - the ticker-tape parades, the press conferences, the flag-waving Texas jingoism - say ''Yes.'' The result: a confused and distorted view of greatness. What the movie gives us is heroism-as-theatrics.
That, in fact, is the danger of ''The Right Stuff'' - that it both reflects and encourages a belief in a glittering heroism that can exist only in fiction. Space is not conquered, and nations are not defended on the basis of that misconception. For heroism is larger than that - a point we need to keep clearly in mind as we make sense of today's real-life military actions. We are not sending articulate chimps into Lebanon and Grenada. We are sending men - real men who, insofar as they are effective soldiers, have goals far beyond swagger and bravado.
Such goals arise from an understanding, however dim, that America is still a place where ''progress,'' as Commager said, is ''a commonplace of experience.'' They don't arise from cinematic hype. If our allies overseas look at America through the lens of this movie, they may be forgiven for shaking their heads in sadness over our penchant for adventurism and our acceptance of superficiality. For that, I am chagrined.