US Intelligence Agencies
The limbs of America’s defence and security establishment all thought Nelson Mandela was a terrorist even until after his presidency in 1999.
Apparently, being granted freedom, openly forgiving those who wanted you dead and winning a democratic election was not enough for the American authorities to declassify Mandela as a threat.
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It was only in 2008, some five years before his death, that Mandela was taken off the list.