Who can explain the facts about Washington fiction?

IF the Pentagon, as its critics have been known to complain, is stranger than fiction, it's going to stay that way for a while. Richard N. Perle has decided not to write the Great American Novel about his life and times as assistant defense secretary. All the early warning systems in Washington went on red alert when the report leaked out that Mr. Perle was negotiating a book contract for $300,000. To guarantee his publishers their money's worth, it is rumored, he promised that his novel would disguise real life as little as possible.

Before you could say ``Mayday!'' Sen. Sam Nunn had filed a protest with President Reagan, using ominous phrases like ``violating a fundamental public trust'' and ``endangering the confidentiality of important national security interests.''

The Pentagon's general counsel descended upon Perle with an investigation of ``conflict of interest'' -- General Dynamics should get such scrutiny!

Perle, who presumably aspired to be the once-and-future Norman Mailer, saw himself being cast as the next Benedict Arnold instead. Denying that he would ever ``reveal sensitive or classified information'' or ``relate the views of individual government officials on matters of national policy,'' Perle threw down his apprentice's quill and surrendered in the face of overwhelming enemy forces, muttering something about avoiding ``even the appearance of impropriety, however insubstantial in fact.''

This is definitely not the language of Marcel Proust -- or even John Ehrlichman. It is just 10 years since Ehrlichman's novel, ``The Company,'' revived the roman `a clef, Washington-style -- a tradition that extends back at least as far as 1879 when Henry Adams published his novel, ``Democracy,'' under a pseudonym, thus providing the reader with a game of double disguises.

Sometimes, in fact, the roman `a clef is an ambush behind which a sharpshooter hides with a stockpile of spitballs. The father of the English novel, Samuel Richardson, set an early example in ``Clarissa'' (1748) by shooting down the Duke of Wharton, caricatured as the villainous Lovelace.

Then again, the roman `a clef is sometimes just a gossip sheet in hard cover. For instance, 1976 also saw the publication of Jacqueline Susann's ``Dolores,'' about the widow of an assassinated president who marries one of the world's richest men.

Does Washington fiction -- whether satire or tittle-tattle -- occur in 10-year cycles? This year, even without Perle, we have Patti Davis's ``Home Front,'' which her mother Nancy Reagan calls ``interesting fiction,'' with the accent on fiction -- a word Patti's father reserves for the memoirs of David Stockman.

Two schools of White House literary criticism, you might say, and they reflect the confused and divided state of most American readers of the roman `a clef. The trouble began when Truman Capote invented the term ``non-fiction novel.'' In 1976, Capote joined Ehrlichman and Susann with his own roman `a clef -- ``Answered Prayers.'' Here he had his alter ego say: ``A report, an account. Yes. I'll call it a novel.''

Perhaps the best advice to Richard Perle is this: Write your novel and call it a memoir. What with historians writing like novelists and novelists writing like historians -- and New Journalists writing like both -- who can tell the difference?

Only a genius could sort out all the intentional and not-so-intentional blurring of fact and interpretation, of which the roman `a clef is just a symptom.

A voice from a decade ago, recycled in 1986, is eager to reduce the confusion. Maureen Dean -- wife of John Dean, who blew the whistle on Ehrlichman, among others -- is coming out in September with a novel titled (are you ready?) ``Washington Wives.'' One more roman `a clef -- or is it? When asked who her characters really are, Mrs. Dean answered, ``I don't think you will recognize any of them. I tried purposefully not to do that. It's total fiction.''

Total fiction! In a year when nothing that's actually happening seems believable anyway, ``total fiction'' could be just what we need.

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