Do Americans view the Mideast through a warped mirror? Double Vision: How the Press Distorts America's View of the Middle East, by Ze'ev Chafets. New York: William Morrow & Co. Inc. 349 pp. $16.95.

Most of Morocco is west of London; Tehran is east of Moscow; Istanbul is north of New York City; Southern Arabia south of El Salvador. In between is the Middle East.

Therein lies the central problem with America's view of the Middle East. No single reporter, not even the well-staffed multibureau operations of Reuters, the Associated Press, and United Press International, can accurately reflect the Middle East. The region is simply too large and diverse.

At any given time, 90 percent of the region is peaceful and normal. Families dine together, children are off to school, youngsters play and dream, workers earn their wages. Yet what many of us think of when we hear the words ''Middle East'' are Arabs and Israelis at each other's throats, or fabulous oil wealth, or mobs of religious fanatics.

If your perception of the United States were shaped only by reports of violence in the South Bronx, of the Mafia, and of one particular religious sect, would you believe that to be an accurate picture? Now, what if reporters deliberately distorted their coverage because of fear or antipathy or idealism - or if they were completely excluded from firsthand observation and instead relied on hearsay from sources with clearly biased motives?

Such is Ze'ev Chafets's argument. In his book, Chafets, former director of the Israeli government's press office (and, thus, a far from neutral observer), expands upon a campaign he began waging two years ago against unfair journalism by Middle East correspondents. Chafets charges that Beirut-based Western correspondents have been intimidated by enemies of Israel and consequently have distorted their news reports in ways that hurt Israel's interests and that run counter to journalistic integrity.

There is much validity to Chafets's argument. Many of the accounts he cites of Syrian assaults on Lebanese and Western journalists in Beirut are, indeed, true. The Palestine Liberation Organization is not blameless either, and Mr. Chafets makes a case for the PLO's having played a version of ''good cop, bad cop'' with reporters in Beirut, thereby molding their news reports.

Chafets also illustrates how Syria, Iraq, and Saudi Arabia systematically exclude objective journalists and cover up news that reflects poorly on the rulers. The 1979 seizure of the Grand Mosque in Mecca, the 1982 massacre by the Syrian Army at Hama, and the entire Iran-Iraq war - all, he charges, have been misreported and underreported.

In most cases, Chafets is right. There are only excuses.

The Western press does what it can to get into these countries, and it reports on events at the sufferance of these regimes. There is little the press can do to change the attitudes of these petty despots - just as there is little the press can do to change the policies of the Moscow Politburo.

Chafets contrasts the closed-door brutishness of Arab countries with the open and lively press coverage of Israel. Again he is right. Israel (about the size of Massachusetts) is an extremely open society. Opposition parties are vociferous and easy to contact. Except during major disturbances, the Israeli-occupied West Bank is highly accessible to Western correspondents, and PLO supporters speak fairly freely.

''It is now fashionable for reporters to be 'neutral,'and 'evenhanded,''' Mr. Chafets complains, ''as if a journalist's neutrality in a contest between open and closed societies is not incongruous. Such 'neutrality' is, in fact, partiality, for it robs Israel of its natural antidote - not the unquestioning approbation of the Western press nor its support for every Israeli action and policy, but its good wishes and affection, and the benefit of the doubt.''

Chafets traces this increasingly distorted view of the Middle East back to 1973, when the first Arab oil embargo hit the West. In subsequent years, he argues, the press - out of an unspoken feeling of national self-interest - leaned more and more in the Arab direction. This was not simply a media whim, he points out; he shows how business and the US administration contributed to this attitude during the Carter years by ''agenda-setting'' in the Middle East.

Is Israel getting a fair break in the Western press? Perhaps not. Perhaps there has been too much of an assumption on the part of Western reporters and their editors that the American public already knows that Israel is open, accessible, and democratic and that most Arab countries are closed and repressive. Perhaps that point needs to be made more frequently by inserting disclaimers into stories filed from Arab countries to the effect that ''this article was subject to censorship'' or ''due to the sensitivity of this subject to the Syrian government this article has been self-censored.''

Mr. Chafets's book is sure to be discounted by many as being Israeli propaganda. It gives short shrift to the argument of many Middle East experts that the press had been overly generous to Israel before 1973. Still, that is no reason for tipping overly in the other direction.

Balance is what is needed - and in an afterword, Mr. Chafets admits that balance is being restored. Clearly, he is not unbiased: It is, he says, now ''reassuring to find the free press of the US on the side of the region's only open society for a change.'' At the same time, he adds, ''this new appreciation of Israel did nothing to change its basic flaws in America's Middle East coverage.''

Taking into account the Chafets/Israeli viewpoint, the book, nevertheless, will be of interest to students of the Middle East, of foreign policy, and of the US media.

It should give reporters and editors pause at least to consider how they convey the news from this huge, diverse region of the world.