Gus Russo was in his first year at a Catholic high school in Baltimore when he heard the news that President John F. Kennedy had been shot. In the days to come, questions about how it happened took different forms, and conspiracy theories abounded.

Since then, Russo, born into an Italian Catholic family that he said “worshiped” the Kennedys, has maintained a fascination with the events leading up to the attack in Dallas on Nov. 22, 1963. It seems he’s not the only one: The assassination has inspired hundreds of books and dozens of films and documentaries. Russo recently released his second book on the subject, “Brothers in Arms: The Kennedys, the Castros, and the Politics of Murder,” co-authored with Stephen Molton.

Russo said this book delves into information that was unavailable when he published “Live by the Sword: The Secret War Against Castro and the Death of JFK” in 1998. He restarted the research in 2003 when German public television approached him about producing a documentary called “Rendezvous with Death.” During that investigation, Russo looked into papers newly released from the National Archives and worked with a source who had access to Russian intelligence.

The narrative’s strength is its depth — even before the afterword, notes, bibliography and index, the book is 470 pages long. Russo and Molton used their new access to Russian intelligence to give ample details about Kennedy assassin Lee Harvey Oswald’s years in the Soviet Union after he defected from the Marines and before he shot the president.

“The KGB service reports created an astonishingly thorough narrative of Lee’s activities,” they wrote. “They chronicled his movie-going habits, every piece of cake and cup of coffee he consumed in public, his stinginess on dates with women he wasn’t enthused about, his preference for blondes, his ignorance of Marxist-Leninist theory, the records and appliances he bought, the hardware stores he visited, and, of course, the friends with whom he consorted.”

Those details fill out what is already common knowledge about Oswald’s rocky childhood and tumultuous stint as a Marine. Later chapters go into depth on the lifestyles and motivations of behind-the-scenes players in Cuba, Russia, Mexico and the United States. It provides context for many of the other decisions that these men and women made and learned from. The CIA, for example, was encouraged by the disorganized but successful overthrow of President Jacobo Arbenz Guzmán in Guatemala in 1954 and had approved of Belgium’s assassination of the prime minister of the Republic of the Congo in 1961.

The book is relevant today not only because of the authors’ new revelations but also because of comparisons that the authors have drawn between the foreign policy of Kennedy and President-elect Barack Obama. Russo, who said he voted for Obama, explained that he is worried Obama will keep some of President George W. Bush’s intelligence advisers on, a move that he said got Kennedy in trouble.

In “Brothers in Arms,” the authors imply that keeping on CIA Director Allen Dulles and his deputy, Richard Bissell, empowered the spies’ intent to oust Castro. After the botched Bay of Pigs invasion, Dulles was forced to resign and Bissell’s resignation from the agency was accepted about a year later.

Writing for the Huffington Post in November, Russo and Molton drew parallels with the incoming Obama administration.

“In his effort to recruit the most current experts to ease his transition, Kennedy staffed key intelligence positions with those tied to President Eisenhower. Keeping much of Dwight Eisenhower’s gung-ho spy apparatus in place was, in hindsight, Kennedy’s greatest miscalculation,” they wrote. “Consequently, his acquiescence to the most extreme sanctions against his perceived enemies dwarfed all his other more inspirational efforts.”

They conclude by saying they hope Obama will learn from Kennedy’s mistakes.

Regardless of whether a reader sees a warning for the future in Kennedy’s foreign policy or just another well-researched theory on the events that led up to Kennedy’s death, “Brothers in Arms” is well worth the time that it requires.