The greatest speech that Dr. King delivered happened just two days before his death. King was a pretty defeated man by April 1968, understanding that his time in this world was nigh. He was the prophet predicting his own demise.
The Memphis Sanitation Worker's strike gave King a bit of a bounce in his step, while he was preparing for the Poor People's March on Washington, the site of King's greatest triumph up until that time. Yet, King took a moment in the Memphis march during what would be his last campaign to fire up his peaceful warriors.
Dark days were ahead, and King was beyond worrying. He had given all he could to advance a movement in the South to finally rip the chains from the sharecroppers and children of sharecroppers where he grew up and cut his teeth as a young preacher. Although the North gave King the money he needed, he saw intense opposition to his own opposition to the War in Vietnam. King's fiery furnace phrase, "I don't fear any man" was less a taunt to his would-be killer(s) and more a challenge to the people who would pick up his historical mantle of direct yet radical non-violent movements four decades later: Us.
In my estimation, politicians are not these peaceful warriors--sorry Barack Obama. High-flying and churchy oratory aside, the next people's leader will come from the fields, jungles, or forests of the developing nations rather than the halls of our current version of the House of Lords, also known as the US Senate.
The new Kings are leading their people in second and third world nations where the grassroots movements can halt the scythe of dictators, industrialized nations, multinational corporations, and time.
There will never be another King in our nation, I fear, because we are all too much in and of this world.