Senator Robert Kennedy made one of the greatest American speeches ever 50 years ago this week on hearing of the death of Martin Luther King, cut down by an assassin's bullet on April 4th, 1968.

Kennedy, running for president, was on the campaign trail but was warned not to go ahead with his rally in a run-down ghetto area of Indianapolis as police stated bluntly they could not protect him from what they felt were almost certain serious violence to come.

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Undaunted, Kennedy went anyway with no protection and gave his speech from the back of a flatbed truck. In that era before the internet, news traveled much differently. Some at the Kennedy rally had heard, most had not. Some who had heard had armed themselves for the violence they saw as inevitable.

Yet Kennedy somehow calmed the crowd as he told them of King’s death. He knew many were ready to riot. Indeed there would be rioting in 34 cities that night, but not in Indianapolis.

He appealed to the crowd’s better angels despite their anger and pain. He acknowledged they could be “Filled with bitterness and with hatred and a desire for revenge,” but he said King would not have wanted it that way. He stated they could riot or “we can make an effort, as Martin Luther King did, to understand, and to comprehend, and replace that violence, that stain of bloodshed that has spread across our land, with an effort to understand, compassion, and love.”

For the first and only time, he cited the murder of his brother and how he had to battle the rage and hate that gripped him when he was gunned down.

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“I would only say that I can also feel in my own heart the same kind of feeling. I had a member of my family killed, but he was killed by a white man,” he said.

He reached back 2,500 years to the Greek poet Aeschylus and quoted him.

“Even in our sleep, pain which cannot forget
falls drop by drop upon the heart,
until, in our own despair,
against our will,
comes wisdom
through the awful grace of God.”

Thirty-four cities rioted that night, Indianapolis was the only large black majority city that did not, mainly due to Kennedy’s eloquence and appeal for calm. It was quite simply his finest hour and an example of leadership rarely matched.