One of the many conspiracy theories about JFK is that he was assassinated because he wanted to do a deal with the leadership in Cuba. Elements within the Spook Agency in Langley and the Mob were not pleased at that so engi9neered his demise.
The largest military airport on the Balkan Peninsula was built for the Warsaw Pact forces in Balchik. It is still there and is used by the Bulgarian Air Force and NATO.
I think you are talking about Kaliningrad. If you are going to pretend to be an expert on international affairs, at least get the name of the city rught.