BY JUAN O. TAMAYO
Special to The Miami Herald

If Kendall and Gwendolyn Myers know their Cuban history, they might well blame their arrest last week on charges of spying for Havana on the 1989 execution of Cuban Army Gen. Arnaldo Ochoa and the 1996 shootdown of two Brothers to The Rescue airplanes.

The first event led to a massive purge at the Ministry of Interior (MININT), in charge of the island's security, that crippled its operational abilities for years afterward and exposed it to U.S. counter-measures. The second made the FBI angry -- really angry.

From 1959 to 1995, only four Cuban spies were arrested in the United States, including three in 1962. The U.S. counterintelligence community's preferred strategy was to watch Cuba's spies and expel them only when they got too frisky. No use arresting or expelling someone and then having to spot the replacements Havana was certain to send, U.S. officials argued. During the Cold War, some 30 Havana diplomats assigned to the Cuban Interests Section in Washington or the U.N. Mission in New York were expelled or denied reentry into the United States.

Through their first three decades, Cuba's five intelligence services -- the MININT's Intelligence Directorate (DI) and Counterintelligence Directorate (DCI), the armed forces' Military Intelligence Directorate (DIM) and Military Counterintelligence (CIM), and the Americas Department of the Communist Party's Central Committee -- were regarded as among the world's best, after the United States, the Soviet Union and Israel. They had massive Soviet and Warsaw Pact support and considered they had only one enemy -- Washington. In contrast, U.S. intelligence regarded Cuba as a second-tier concern, after big-trouble countries like Russia, China, North Korea and Iran.

Prosecution documents filed in the Myers case allege they were recruited by Cuba in 1978 -- right in the middle of Cuba's intelligence apex, when the romance of the revolution and the bearded Fidel Castro were attracting widespread support around the world.

But then came 1989 and Cuba's firing-squad executions of Gen. Ochoa, MININT Col. Tony de la Guardia and two other security force officers on charges of drug running. Some 300 MININT officers were purged, and many were replaced by military officers with little experience in intelligence. Several DI and DCI officers defected and provided valuable information to Western intelligence services.

By 1995, U.S. counterintelligence had become aware of at least part of the Avispa (Wasp) spy network in South Florida. But Justice Department officials in Washington were initially reluctant to arrest and prosecute its members. ''Too aggressive,'' they argued.

The green light came only after investigators linked some of the spies to the Brothers to The Rescue shootdown, which killed four U.S. residents. The FBI in South Florida was especially angry because it had been using Juan Pablo Roque as a paid informant at the same time he was reporting back to his Cuban handlers about the activities of the exile group, formed to fly over the Florida Straits and help safeguard Cuban rafters fleeing the island.

The U.S. reluctance to arrest and prosecute had been shattered.

Sept. 1998 -- Ten Avispa members were rounded up. Five cooperated with U.S. authorities and received lighter sentences. The others chose to go to trial, were convicted and sentenced to long prison terms. More than 20 others fled abroad or into deep cover within the United States.

Feb. 2000 -- Mariano Faget, Cuban-born veteran of the U.S. Immigration and Naturalization Service, was sentenced to five years.

Aug. 2001 -- Avispa members George and Marisol Gari pleaded guilty. He got seven years in prison, she 3 ½.

Sept. 2001 -- Ana Belen Montes, a senior analyst at the Pentagon's Defense Intelligence Agency and the top Cuba spy ever caught, was arested. She pleaded guilty and was sentenced to 25 years.

May 2002 -- Avispa member Juan Emilio Aboy is arrested. He was deported in 2005.

Jan 2006 -- Carlos Alvarez and wife Elsa Prieto, FIU professors, are charged. They pleaded guilty. He got a five-year sentence; she got three.

June 2009 -- Walter Kendall Myers, 72, and his wife, Gwendolyn Steingraber Myers, 71, are arrested. He was a top official at the State Department's Bureau of Intelligence and Research, she a senior bank systems manager. They have pleaded not guilty.

It's interesting to note that Walter Myers was a longtime professor at the Johns Hopkins University's School of Advanced International Studies, where Montes earned her masters' degree in 1988 -- and where U.S. intelligence officials say she was marked for recruitment by a Cuban intelligence talent-spotter at the university.

U.S. spy-catchers say Cuban intelligence focuses its trolling for potential American spies on the four Washington-area universities whose international studies programs regularly send their graduates to key positions throughout the U.S. government -- Johns Hopkins, Georgetown, American and the University of Virginia. ''The Cubans fish in a small pond,'' said one.

It will take time for more details of the Myers' case to become public. Some may never see the light of day -- how the FBI stumbled on to their spying, who their Cuban contacts were, how much damage they caused.

But whatever the results of the damage assessment, within the U.S. intelligence community there's little doubt that the Myers couple was NOT the last of the Cuban spies.

Chris Simmons, a retired Pentagon expert on Cuban Intelligence who helped uncover Montes' spying, estimates that Havana maintains approximately 250 agents and agent-handling officers in the United States -- a robust effort though smaller than during the Cold War, when some 300 were operating in Florida alone.

Based on past Cuban ''tactics, techniques, and procedures,'' Simmons said, the 250 would include six to nine senior agents within the U.S. government similar to Montes, more than a dozen in academia and 30-36 under diplomatic cover at Cuban missions in Washington and New York.

Another 135 or so, he added, are likely to be keeping an eye on Cuban-Americans, mostly in South Florida.