Can American commercial television blend entertainment and moral enlightenment successfully? Prime-time televison used to tiptoe delicately through the electronic mine fields of its own industry-wide taboos. Certain topics - mainly abortion, sexual promiscuity, homosexuality, and incest - were for the first 25 years of TV regarded as too ''touchy'' to be touched, certainly in drama and even in most newscasts. Daytime soap operas, however, broached the taboos at will.
Then, to win larger audiences for local news shows, segments featuring tentative investigations of the taboos began breaking through. Entertainment television learned the lesson quickly and began using ''taboo'' subjects in filmed dramatizations. Sometimes, the material was presented honestly as public-service-oriented docudrama. But too often it was exploitation and titillation masquerading as honesty.
There are those who would argue that our society was changing as well, that those taboos had become more generally acceptable in the community and therefore valid material for dramatization. Whatever the reason, these topics have become a staple of entertainment television, providing new thrills for jaded viewers.
Since the early 1970s, we have seen more prime-time dramas dealing with ''forbidden themes.'' Often the subjects have been handled delicately, to avoid the wrath of the would-be censors. And in some instances - as in the case of ''Adam,'' the recent NBC drama about missing children - the dramatization results in greater awareness of a real problem. But too often that aim is only a ploy to make the drama more acceptable.
This season, the problem-of-the-week, made-for-TV films have included dramas about white slavery, call girls, pornographic photography, and massage parlors. This week there is a drama about drunken driving (License To Kill, CBS, Tuesday, Jan. 10, 9-11 p.m.). And ABC, the network that so recently stirred up controversy with ''The Day After,'' is going back eagerly to the trough of contention with Something About Amelia (Monday, Jan. 9, 9-11 p.m.). It is a drama about what has heretofore been regarded as the most untouchable subject of all: incest.
Together, these two programs are prime examples of today's relevant-or-bust genre of entertainment films. It is difficult to condemn them outright: Both seem on the surface to be well-intentioned and germane to problems in contemporary society. But could they have accomplished more if handled honestly in nonfiction fashion?
Are serious problems, in other words, proper material for lightweight TV entertainment?
Few could object to skillful and literate treatment of delicate personal material - writers throughout history have chosen such themes. But television - especially prime-time commercial television, with its too-often mechanical writing level - is a unique and dangerously sensitive medium, one which integrates itself immediately into the physical as well as the psychological environment of its viewers.
Once TV treats a subject as light dramatic entertainment, can it be easily switched back into the area of serious problem solving? That's the question commercial entertainment television must cope with sooner or later if it wishes to be honest with itself.
'License to Kill'
The final legend - ''Every 23 minutes one life is lost in an alcohol-related accident'' - is probably the most shocking moment in ''License to Kill.''
This well-meaning, understated, cliche-ridden little soap opera of a drama reads like a case history. The utterly devastating effect of a fatal car accident caused by a drunk driver on the families of the victim and of the perpetrator is handled with almost clocklike predictability.
Acted with skill by James Farentino, Don Murray, and Penny Fuller, smoothly directed by Jud Taylor, ''License'' is so loaded with good intentions and incontrovertible morality that it is difficult to fault it on any level - except that scriptwriter William A. Schwartz has made it sudsy when it needs to be flinty. But if ''License'' deters even one driver from drinking, it will have served a valuable function.
'Something About Amelia'
On the other hand, whether or not ''Something About Amelia'' will serve a function other than titillation is unclear.
According to the University of Indiana Sex Institute, 3.9 percent of the population - about 9 million Americans - have been involved in incest. ''Amelia'' is aimed mainly at those people.
Handled with restraint, the film follows a 13-year-old girl's disclosure to her school guidance counselor of her father's crime, the psychological treatment for all involved, and the attitude of the social workers and the courts as well as family and friends. William Hanley has written a tight, flat skeleton of a script, which is directed with an imperceptible touch by Randa Haines and acted with a poker-faced believability by Ted Danson of ''Cheers'' fame. There are no sexually explicit scenes and very little objectionable dialogue.
However, many people may rightfully object to the fact that the film has been made as an entertainment. Incest is a delicate and sensitive subject, needing expert care to avoid frightening unsophisticated viewers. So, quite apart from the merits of this particular, rather skillfully done show, the question remains whether this case-history dramatization is a proper subject for an evening's entertainment.
A chat with the producer
Executive producer Leonard Goldberg, co-producer of ''Hart To Hart,'' ''Fantasy Island,'' and ''Charlie's Angels,'' interrupts a skiing vacation in Snowmass, Colo., to chat about ''Amelia.''
Why the dramatic form rather than a documentary form?
''Well, first of all, I am not a documentarian. Of course, a documentary could do the job effectively. But the dramatic form gives it an added dimension. You can draw the audience into the story, get them involved so that the message can be more effectively delivered.''
And what is the message?
''There is a tremendous social problem in this country called incest. We have pretended that it doesn't exist for a long time. We want people to realize this problem exists and that it must be dealt with. Government and social agencies have done very little to help in this area. . . . We want everybody to address the problem. We want to say to all the people out there with incest problems - it is OK to step forward and admit that you or someone you know has the problem, because the only way to begin to solve the problem is to admit that it exists.''
Mr. Goldberg has a nine-year-old daughter. Will she watch the show?
''Psychologists say that children should watch it with their parents. Younger kids won't understand it. Older children will get more from it. My daughter is usually in bed by 9, but that's a cop-out. The truth is I am still wrestling with the decision as to whether or not to allow her to see it.''
ABC is planning to encourage local affiliated stations to arrange for ''hotlines'' so that children and parents affected have a place to call for help. Mightn't that result in family-shattering ''tell on Daddy'' calls to police?
''I hope it won't be to the police, but to the most appropriate social agencies in each area.''
Are there any topics Mr. Goldberg believes not proper for entertainment television?
''It all depends upon how the subject is handled. I think some of the senseless violence I see on TV is more objectionable than delicate subject matter like 'Amelia.' ''
Mr. Goldberg was off the phone and on his way to the slopes before I could ask him if, perhaps, some of that objectionably handled subject matter had appeared on ''Charlie's Angels.''