We've known for decades that the FBI waged a campaign of harassment against Martin Luther King which culminated in attempts to goad him to commit suicide or face public revelations about sexual liaisons the Bureau had uncovered through pervasive surveillance. We've also known for years that there was a 1964 letter to King leveling this threat. Until now though we've known about the letter but only in a highly redacted form. Now the full letter is available. Jarring but important to see.