Muhammad Ali's refusal to sign his Vietnam-era military draft card upended the boxing champ's life and added a powerful voice to the anti-war movement. Now that piece of history is coming up for sale.

Muhammad Ali’s refusal to sign his Vietnam-era military draft card upended the boxing champ’s life and added a powerful voice to the anti-war movement. Now that piece of history is coming up for sale.

Muhammad Ali's refusal to sign his Vietnam-era military draft card upended the boxing champ's life and added a powerful voice to the anti-war movement. Now that piece of history is coming up for sale.

Muhammad Ali’s refusal to sign his Vietnam-era military draft card upended the boxing champ’s life and added a powerful voice to the anti-war movement. Now that piece of history is coming up for sale.

A pivotal piece of history, Muhammad Ali’s unsigned Vietnam-era military draft card, which profoundly altered the boxing legend’s life and amplified the anti-war movement, is now set to go up for sale ...