The release of thousands of secret documents from the JFK assassination contains little new information and no bombshells.  But for the legion of amateur assassination buffs and historians, there are some fascinating glimpses into the thinking of government officials and the alleged assassin's actions.

Here are a few highlights compiled by CBS Miami:

Sabotaging plane parts

A national security council document from 1962 – before Kennedy's murder – referenced "Operation Mongoose," a covert attempt to topple communism in Cuba.

In the minutes of a secret meeting on Operation Mongoose from September 14,1962, "General (Marshall) Carter said that the CIA would examine the possibilities of sabotaging airplane parts which are scheduled to be shipped from Canada to Cuba."

CIA-mafia plot on Castro

A 1975 document from the Rockefeller Commission detailing the CIA's role in foreign assassinations said plans to assassinate Castro were undertaken in the early days of the Kennedy administration.

The report said Attorney General Robert Kennedy, the President's brother, told the FBI he learned the CIA hired an intermediary "to approach Sam Giancana with a proposition of paying $150,000 to hire some gunman to go into Cuba and kill Castro."

The attorney general said that made it hard to prosecute Giancana, a Sicilian American mobster.

"Attorney General Kennedy stated that the CIA should never undertake the use of mafia people again without first checking with the Department of Justice because it would be difficult to prosecute such people in the future," the report reads.

The report also said the CIA was later interested in using mobsters to deliver a poison pill to Castro in order to kill him.

During Operation Mongoose in 1960, the CIA also considered staging terror events in Miami and blaming it on pro-Castro Cubans.

There's little doubt that neither Eisenhower or Kennedy – nor CIA directors Allan Dulles and Richard Helms – would have signed off on a plan to stage "terror events" in Miami.  But it shows a previously unknown level of how desperate the CIA was to get rid of Castro.

The FBI got a death threat on Oswald the day before his murder

A document dated November 24, 1963, showed FBI Director J. Edgar Hoover addressing the death of Oswald at the hands of Jack Ruby.

"There is nothing further on the Oswald case except that he is dead," Hoover begins.

Hoover said the FBI's Dallas office received a call "from a man talking in a calm voice," saying he was a member of a committee to kill Oswald.

He said they pressed the Dallas chief of police to protect Oswald, but Ruby was nevertheless able to kill the gunman.

"Ruby says no one was associated with him and denies having made the telephone call to our Dallas office last night," Hoover said.

If the mob hit Oswald, it is extremely unlikely that they would alert the FBI beforehand.  That call was one of dozens of threats against Oswald received by law enforcement.

In the years following the assassination, the hunt was on to find a Soviet or Cuban connection to Oswald.  Some conspiracy theorists will go to their grave believing in KGB or Cuban involvement in the assassination.  But while there is some smoke, there is nothing solid to prove it.

Hoover went on to say the FBI had evidence of Oswald's guilt and intercepts of Oswald's communications with Cuba and the Soviet Union. He said he was concerned there would be doubt in the public about Oswald's guilt and that President Lyndon Johnson would appoint a commission to investigate the assassination.

At this early date, Hoover was well aware of Oswald's trip to Mexico City in September of 1963.  That's because the FBI had him under surveillance.

Alleged Cuban intel officer said he knew Oswald

A cable from the FBI in 1967 quoted one man quipping Oswald must have been a good shot.

The alleged Cuban officer returned, "oh, he was quite good."

Asked why he said that, the officer said, "I knew him." ...

CIA intercepts call from Oswald to KGB

A CIA memo from the day of Kennedy's assassination outlined a CIA intercept of a call from Oswald, then in Mexico City, to the Russian embassy in Mexico. Oswald spoke to the consul, Valeriy Vladimirovich Kostikov, an "identified KGB officer" "in broken Russian."

The memo's author said he was told by the FBI's liaison officer that the bureau believed Oswald's visit was to get help with a passport or visa.

Again, it's highly unlikely that Oswald knew he was talking to a KGB agent.  He simply wanted help getting a visa to Cuba, after realizing he was a total failure in America.  He yearned for the celebrity of the defector he experienced when he arrived in the Soviet Union in 1959.  But Castro wanted nothing to do with him, and the KGB turned him down flat.

The Warren Commission erred when they stated flatly that there was "no evidence" of a conspiracy.  In fact, there is plenty of circumstantial evidence for Oswald being involved with Cubans, the Soviets, the mob, the CIA, and maybe even the FBI given the possibility he was an informant. 

But these documents shed no light on Oswald's associations, and therefore, any conspiracies connected to the assassination remain in the realm of speculation.