Washington (CNN) -- "I'm going to appoint Thurgood Marshall to the (Supreme) Court." This monumental, unexpected bombshell from President Lyndon Johnson -- spoken in private in the summer of 1965 -- set in motion a history-making drama, revealed for the first time in newly public audio tapes. In secret recordings and transcripts made exclusive to CNN, Johnson laid out a politically crafty plan that was years in the making to groom Marshall as the first African-American on the high court. It was part of a broader White House strategy to implement the president's civil rights agenda, something he openly hoped would cement his legacy and strengthen the Democrats' base.
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Secret tapes of President Lyndon Johnson released exclusively to CNN
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Tapes reveal president's long-term aspirations for Thurgood Marshall
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Johnson carefully laid out a path for Marshall to join Supreme Court, tapes show
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LBJ on Marshall: "I want to build him up where he's impenetrable"
By the time of his government appointments, @placeholder was in his mid-50s and itching for new challenges.
But it is clear from this conversation that LBJ is using Marshall's grooming for the Supreme Court as the model he will use to boost other outstanding @placeholder candidates to senior government positions.