Tuskegee Syphilis Experiment

While reading the chapter in Medical Apartheid and the article, I was very surprised by the Tuskegee experiment. I was more interested in the time period when it happened and how no one knew about this. Rural, poor, black men who were thought to be infected with Syphilis were taken in and told they were going to be cured of their disease. The PHS used these men to see what affects the disease has on their bodies. How were all of the doctors okay with treating their patients like this? Did any of the doctors speak out against the experiment because they thought it was wrong? Did they feel it was okay to perform these experiments because they were black? If it was a legit study they would not discriminate against race, leading me to believe that there was an underlying reason to the Tuskegee experiment.