STRIPPED OF all the maudlin martyrdom, former congressman Paul Findley's message is straightforward and valid: Israeli influence in the United States, including in the inner sanctums of government, is very strong.

Sometimes this influence is brought into play with the utmost of subtlety and sophistication. On other occasions, if it seems a good bet to work, influence is exerted with a crudeness that leaves purveyors of other special interests aghast -- and not a little envious.

Sometimes this so-called Israel Lobby (in reality, it should be "Lobbies," for the influence is not always monolithic) succeeds in its various intents; sometimes it fails.

Anyone familiar with the American political process is likely to greet this message with an only slightly suppressed yawn. The energy and tenacity of Israeli representatives and their American sympathizers -- many, but not all, of them Jews -- has long been acknowledged by legislators and civil servants at national, state and local levels.

For Mr. Findley, however, the subject has particular pertinence. After 22 years of quietly representing Springfield, Illinois, in the House of Representatives, he found himself singled out as a special target of Jewish political activists; he had committed the "indiscretion" of becoming friendly with Yasser Arafat, chairman of the Palestine Liberation Organization.

Voted out of office in 1982, after a bitter and close campaign, he promptly set out to investigate the powerful influences that had worked to defeat him. This provocative and highly selective portrayal of an interest group at work raises more interesting questions than it answers.

Numerous Israeli memoirs and histories have long since put on record ample detail of successful Zionist penetrations of the American power structure in the late 1940s. Political influence was sometimes effective in the drive to gain recognition for the State of Israel; far more impressive was the network of clandestine arms shipments, in clear violation of American law, which operated under the cooperatively averted eyes of J. Edgar Hoover.

Not surprisingly, engaged Israelis and Americans have been less forthcoming about their more recent endeavors, but there is every reason for onlookers to assume that the techniques of persuasion and information-gathering that worked so well back then have continued to serve their varied purposes. Mr. Findley has not discovered anything new in his investigations, even if many people involved are hesitant to speak freely.

THIS RAISES the interesting questions too seldom discussed. Why should people like Mr. Findley consider it an act of great personalcourage to assert the strength of Israeli influence, a fact of public life that is already well known and assimilated?

And secondly, just why is this Israeli influence so strong? Is it a foreign conspiracy against the interests of the Republic, engineered by present-day Elders of Zion? Or might it possibly be that a significant number of Americans, strange as it may seem to those who feel otherwise, genuinely entertain some degree of sympathy for the concept of Israel? Such a possibility has no place in Mr. Findley's quest for conspiracy.

To his credit, the disappointed incumbent confines his personal problems to a modest, though revealing introduction. But the tone of anguished martyrdom -- his own and that of other stalwart Americans -- begins right away with a listing of the publishers who decided not to buy the manuscript of this book. (If every author chose to deliver such testimony, book introductions would become tedious indeed.)

Yet the point is not entirely irrelevant. It is a fact that many people and institutions shy away from discussion about how powerful Israeli interests have been and can be, a reticence not so marked with the old China Lobby, the Greek or Armenian interest groups of today, to say nothing of organized labor, the National Rifle Association or the Right to Life movement, to name just a few.

There is an obvious explanation, with roots deep in past generations. Depictions of Jewish cultural or economic "power" in gentile society -- whether demonstrated in sympathetic analysis or, more often, exaggerated with nuance and falsehood -- have served for a century and more as thinly veiled expressions of anti-Semitism. Logically, this is absurd; historically, it is fact.

Anti-Semitism is a grave charge, and activists from the Jewish Community Council of Tucson (an example dwelt upon by Mr. Findley) all the way to the broken prime minister of Israel, Menachem Begin, do no honor to the intellectual integrity of their heritage if they throw the charge around loosely, whenever they hear anything they do not like.

But the matter does not end there. Non- Jews have the obligation to ask themselves if they are indeed free from anti-Semitic instincts when they single out Jewish influence for criticism. Sometimes I suspect they are not. Two recent instances:

In the uproar over President Reagan's visit to the Bitburg cemetery last May, we heard many comments that "only Jews" were concerned that presidential honor to fallen members of the Nazi SS might not be the most worthy of messages to be convyed to a new generation of Germans, Americans and other peoples.

More recently, Muslim massacres of Palestinians in Beirut's Sabra and Shatila refugee camps brought none of the international outcry that had erupted in 1982 when Israel had shared indirect responsibility for comparable killing. Were Palestinian suffering and carnage less outrageous this time, for not being even indirectly perpetrated by Israel?

Ideological pressures on academic institutions for their Arab Studies programs, which Mr. Findley dwells upon with compelling interest, are indeed offensive -- assuming, of course, that proper diligence has been observed to insure that political propaganda has not crept into the curriculum. The same outrage should be expressed at any community pressures to censor schools and libraries on any moral, religious or partisan grounds.

It is not clear from his writing or his political odyssey that Mr. Findley is aware of these broader considerations in American life.

His book cannot be used as a reference source, for its uncritical treatment of his sources: remarks which cast Israeli interests in a sinister light are conveyed with lip- smacking gusto; assessments which do not fit the pattern are given, at best, cursory treatment.

For his knowledge of Middle Eastern politics, Mr. Findley often relies upon the insights he gained from Arafat. On American policy he cites George Ball, whose wisdom is immense but whose partisanship in Arab-Israeli matters is undenied. One has the feeling that, in scanning the spectrum from Arafat to Ball, Mr. Findley may not have the whole picture.

The most promising note in this investigation -- though it is hardly the point Mr. Findley set out to convey -- is that many of the crude pressure tactics he relates were in fact resisted, and successfully defied. The strong- minded academic dean and television executive and student newspaper editor can in fact stare down a pressure group. So can the congressman -- if he is sure of the ground he stands on, and honest about his motives.