Reading Gretchen Rubin's "Forty Ways to Look at JFK" is like watching tennis. Serve. Volley. Volley. Point.

For 40 chapters, she makes the argument for the good JFK — valiant, witty leader of the New Frontier, inspiration of the early '60s generation, stalwart husband and father, civil rights crusader — point- and counter-pointing against the evil JFK.

That would be the John F. Kennedy who was more style than substance, bought and paid for by his father, a sickly, drug-dependent libertine and unparalleled philanderer and presidential bumbler.

Rubin used the same approach in a book about Winston Churchill, another character on the world stage who had detractors and advocates in abundance. With Churchill, she had much more to work with.

Kennedy, dead at 46, required stretching the material to fill. (Noteworthy: Rubin said among the next subjects she is considering for her next "40 Ways" project is Jesus Christ, who left this world at 32 or 33 by most reckonings.)

After all, until the PT-109 incident — which was a disaster turned into a triumph largely due to father Joe's considerable publicity muscle — JFK was a rich child who was far more interested in his next sexual score and battling a host of illnesses in a world where modern drugs still weren't commonplace.

John Kennedy had two successes as an author — "While England Slept" and "Profiles in Courage" — that have been the source of serious debate about who actually wrote them. Every Kennedy triumph is looked at for the dark cloud that inevitably seemed to be part of any silver lining.

Yet through fate, Daddy's dollars and overwhelming personal charm and panache, he made it to the White House, where he presided over crises that Rubin points out were largely of his own doing.

Whether you are a Democrat or Republican, Kennedy lover or hater, there is much to like about Rubin's effort.

As the author noted, she often marveled how both sides of a case could be artfully and credibly argued when she was a Supreme Court clerk for Sandra Day O'Connor.

She concludes with her own judgment on Kennedy, and while not completely spilling the beans, she makes a case for the circus over the opera, so to speak.

Meanwhile, Brit investigative reporter Matthew Smith offers up a book that purportedly links the death of Marilyn Monroe, the assassination of Kennedy brothers John and Robert, and Ted Kennedy's undoing at Chappaquiddick to a giant conspiracy designed to keeping any and all Kennedys from power. Perpetrator? Lyndon Johnson.

But we can turn to Rubin for some paragraphs on the general issue of conspiracy that effectively passes judgment on Smith's work:

"By far, the great preponderance of eyewitness testimony, physical evidence, and the most advanced analysis of photographs, footage and recordings prove that Lee Harvey Oswald, acting alone killed John F. Kennedy.

"If overwhelming evidence shows that Oswald, acting alone was the killer, why is the belief in conspiracy so deep and so persistent?

"... Preferring the dull simplicity of the truth, the public welcomes the heady mix of details of the assassination and the improbable accounts. ... Therefore no investigation, no evidence, no authoritative report will ever be able to put to rest the cherished mystery of Kennedy's death."

Which should keep Kennedy book reviewers busy for years to come.

"Forty Ways to Look At JFK" by Gretchen Rubin; Ballantine Books ($24.95).