If violations of emotional privacy pain you, as they do me, you probably found Barbara Walters' interview with the parents of John Hinckley Jr. painful indeed.

The Hinckleys have been accused by psychiatrist Thomas Szasz of mounting a "publicity campaign" designed to establish themselves as loving parents, and their son as a victim of schizophrenia, all to some ulterior and less-than- disinterested purpose.

Szasz, who is fiercely hostile to the "insanity plea" successfully entered for young Hinckley, may be right. But the senior Hinckleys don't come across as self-serving to me. Rather, their interview struck me as a convincing portrait of shattered innocence and insularity.

By innocence, I mean the peculiarly late-20th-century condition of middle- class American folk for whom fortune has been at once bountiful and treacherous.

When it was first discovered who had shot President Reagan and three others on that March day in 1981, you heard everywhere that stupid term, "all-American family." Here was a would-be assassin who was not from a shabby back street but from a sort of picture-book idyll of comfort and stability.

Of course, the "all-American family" exists only in the master catalogue of bad journalistic clich,e. But clich,es are useful, and outwardly the Hinckleys fit the "success story" myth: fortunate in business, well-to-do, living in one of those pretty, ubiquitous suburbs.

The Hinckleys seem to have accepted the myth themselves. John Hinckley Sr. told Walters: "We thought we were about as typical and middle class as you could get." They worshiped the Calvinist God, paid their taxes, voted Republican and tried to be dutiful citizens. Their numbers are legion in this country of democratized privilege.

Now, however, they reveal in the Barbara Walters interview a sense that they were living in a cocoon when their lives were jarred by their son's crime.

They were, for example, innocent of insight--either of the formal psychological kind or of the kind that arises from wide reading and experience with people: the educated heart. So that while they sought medical help when their son didn't seem able to find himself, they could by their own account entirely miss the point of his emotional flatness. "He never laughed, he never cried, he never yelled, he never screamed, he never got angry." In this affective poverty, they found nothing especially strange.

On the social or political side, the senior Hinckleys told Barbara Walters that they now find former views and presumed allies wanting. John Hinckley Sr. still "loves" Ronald Reagan, he said, but he would no longer call himself an "archconservative." For one thing, "most of the unfair criticism" of the insanity defense, and some of the "worst proposals" for changing it, "came from the more conservative element."

Other issues now don't seem as clear-cut, as black-and-white, as before --concerning which it should be said parenthetically that the discovery of complexity is scarcely an "archconservative" monopoly. It can happen whenever unexamined social and political attitudes are found, under sudden stress, not to square with basic human needs and duties.

Altogether, this painful interview suggests quite a lot about the puzzle and paradox of the comfortable life in America, with its stereotyped "success stories" and "all-American families."

It is possible in these idyllic settings to miss much until tragedy demonstrates, as it has a way of doing, that it is no respecter of appearances or journalistic clich,es. Most of us pray to be delivered from such an awakening, but the awakening as the Hinckleys describe it seems to me good, and not a contrivance, as Szasz would have us think.

"We've both become much more aware that Thoreau was right, that the mass of men do lead lives of quiet desperation." At this ingenuous confession by John Hinckley Sr., you can almost hear derisive laughter from the back-row seats. For me, however, it had the sound of authenticity. The Hinckleys have discovered that there are more things in heaven and Earth than were dreamed of in their former philosophy. It has been a very expensive education of the heart. Maybe there is something in it for the rest of us, too.