First of all, the Soviet Union wanted to exchange spy pilot Powers for Abel, the reason being that they wanted to return their spy. East Germany wanted to use American students in exchange for Abel. The reason was that it wanted to demonstrate its status as an independent and sovereign country through this exchange.
The Soviet Union did not recognize Abel as a Soviet citizen, so they exchanged hostages through East Germany, and East Germany was the younger brother of the Soviet Union at that time, but the United States did not recognize the East German regime. For the United States, the Soviet Union and East Germany are actually the same thing.
Negotiations with the Soviet Union went smoothly, and after a little negotiation, an agreement was reached. However, East Germany was unhappy, thinking that the United States did not attach importance to East Germany, so they decided to replace them with two, and it was not obvious to them, and it was not recognized by the United States. Donovan told the East German side, either one for two, or none at all. East Germany did not dare to spoil the Soviet Union's big brother, so in the end it was still a compromise.
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