The man best known for popularizing the term "Black power" always answered the phone with the words, "ready for revolution."

Stokely Carmichael answered the phone this way to acknowledge his role in sacred efforts to build a new society in America and around the world. He defined revolution as transforming the status quo relationship between world systems and societies, institutions and citizens.

Carmichael, who replaced John Lewis as head of the Student Non-Violent Coordinating Committee in 1966, led the largest anti-war demonstration of the 1960s and marched alongside of Martin Luther King Jr. He died of cancer at 57 in 1998 but would have turned 80 on June 29; his legacy casts an enormous shadow (no less than Malcolm X and Martin Luther King Jr.) over 21st century Black politics.

This milestone birthday of Carmichael's is a moment to observe how today's Black politics still bears the imprint of an icon who remains underappreciated and misunderstood to this day.

For many, Carmichael will always remain the 24-year-old firebrand who sparked a global political revolution by shouting "Black power!" to exhort a crowd while marching down Mississippi's Highway 51 arm in arm with Dr. Martin Luther King in the late spring humidity of June 1966. Carmichael had been jailed with future Congressman John Lewis, parried verbally with writer James Baldwin in 1963 as a student at Howard University when Baldwin was invited to campus, listened to Malcolm X speak as a college freshman and served as a bodyguard and driver for King, whom he considered a beloved friend and mentor, in the Mississippi Delta.

"In order for America to really live on a basic principle of human relationships, a new society must be born," observed Carmichael during a 1966 speech at the University of California at Berkeley. "Racism must die," he continued. "The economic exploitation of this country of non-white peoples around the world must also die -- must also die."

The parts of Carmichael's activism that focused on economic justice -- he became a socialist during the second half of his life -- remain more important now than ever. Carmichael's legacy spans the movement for Black power, the push for voting rights in the 21st century and the recent political campaigns that have given voice to those seeking more radical change -- including socialists, community organizers and Black Lives Matter activists.