Final answer:
John Lewis was unable to join the Student Nonviolent Coordinating Committee (SNCC) as it was banned in Alabama. Despite facing violence and arrest, he continued advocating for civil rights and led key actions such as Bloody Sunday.
Step-by-step explanation:
The organization that John Lewis was unable to join due to it being banned by the state of Alabama was the Student Nonviolent Coordinating Committee (SNCC). Lewis had become a key figure in the Civil Rights Movement at a young age, recognized for his leadership and commitment to challenging the injustice of Jim Crow segregation. Even though he faced many dangers and violence, including severe beatings by mobs and law enforcement, Lewis remained steadfast in his belief in nonviolence and continued to fight for civil rights, eventually leading more than 600 peaceful protestors across the Edmund Pettus Bridge in Selma, Alabama, in a historical event known as "Bloody Sunday." His leadership in SNCC and his role in significant civil rights actions, such as voter registration drives and sit-ins, were crucial in shaping the movement and pushing towards change in legislation and civil liberties.