Realpolitik. He’s no dummy
After he was president, Nixon gave a great speech to the student union at Oxford, England. He spoke about how criticizing the Soviets outwardly (or any country for that matter) on how they treated their own citizens wasn’t the way to change things.
He spoke about how he never used the issue for politics, but behind the scenes would link some of the deals with the USSR to letting the Jews leave the USSR. And he was given a hard time for not using the press and calling for more freedom for the Jews. But he said that was the USSR’s internal affairs, and lambasting their leaders would just make them look weak and harden their resolve to let the Jews leave.
Then he recited the numbers of Jews that were allowed to leave the USSR - both before and after he was in office. It was pretty amazing the contrast. Something like a hundred Jews before and after, and thousands (tens of thousand??) each year that Nixon was doing things.