In April of 1967, Muham­mad Ali arrived at the U.S. Armed Forces Exam­in­ing and Entrance Sta­tion in Hous­ton, Texas. “Stand­ing beside twen­ty-five oth­er nerve-racked young men called to the draft,” writes David Rem­nick at The New York­er, Ali “refused to respond to the call of ‘Cas­sius Clay!’” Offered the choice of going to Viet­nam or to jail, he chose the lat­ter “and was sen­tenced to five years in prison and released on bail.” Ali lost his title, his box­ing license, his pass­port, and — as far as he knew at the time — his career. He was new­ly mar­ried with his first child on the way.

When Ali refused to go to Viet­nam, he was “already one of America’s great­est heavy­weights ever,” notes USA Today. “He’d won an Olympic gold medal for the Unit­ed States in Rome when he was just 18 and four years lat­er, against all odds, defeat­ed Son­ny Lis­ton to win his first title as world cham­pi­on.” Ali, it seemed, could do no wrong, as long as he agreed to play a role that made Amer­i­cans com­fort­able. He refused to do that too, becom­ing a Mus­lim in 1961, chang­ing his name in 1964, and speak­ing out in his inim­itable style against racism and Amer­i­can impe­ri­al­ism.

Ali stood on prin­ci­ple as a con­sci­en­tious objec­tor at a time when resist­ing the Viet­nam War made him extreme­ly unpop­u­lar. Sports Illus­trat­ed called him “anoth­er dem­a­gogue and an apol­o­gist for his so-called reli­gion” and pro­nounced that “his views of Viet­nam don’t deserve rebut­tal.” Tele­vi­sion host David Susskind called him “a dis­grace to his coun­try” and even Jack­ie Robin­son felt Ali was “hurt­ing… the morale of a lot of young Negro sol­diers over in Viet­nam.”

Robin­son gave voice to a sen­ti­ment one hears often from crit­ics of polit­i­cal­ly out­spo­ken ath­letes: “Cas­sius has made mil­lions of dol­lars off of the Amer­i­can pub­lic, and now he’s not will­ing to show his appre­ci­a­tion to a coun­try that’s giv­ing him, in my view, a fan­tas­tic oppor­tu­ni­ty.” But the coun­try also gave Ali the oppor­tu­ni­ty to take his case to the Supreme Court, as his lawyer told Howard Cosell in the ABC news seg­ment at the top. “Ali had no inten­tion of flee­ing to Cana­da,” DeNeen L. Brown writes at The Wash­ing­ton Post, “but he also had no inten­tion of serv­ing in the Army.”

Ali strung togeth­er a liv­ing giv­ing speak­ing engage­ments at anti-war events around the coun­try for the next few years as he fought the ver­dict. It was hard­ly the liv­ing he’d made as cham­pi­on. But “my con­science won’t let me go shoot my broth­er, or some dark­er peo­ple, or some poor hun­gry peo­ple in the mud for big pow­er­ful Amer­i­ca,” he said. “And shoot them for what? They nev­er called me [the N word], they nev­er lynched me, they didn’t put no dogs on me, they didn’t rob me of my nation­al­i­ty, rape and kill my moth­er and father…. Shoot them for what? How can I shoot them poor peo­ple? Just take me to jail.”

Ali remained promi­nent­ly in the pub­lic eye through­out his appeal. He had become a “fix­ture on the TV talk show cir­cuit in the pre­ca­ble days of the 1960s and ‘70s,” writes Stephen Battaglio in a LA Times review of the recent doc­u­men­tary Ali & Cavett. He remained so dur­ing his hia­tus from box­ing thanks in no small part to Dick Cavett, who had Ali on fre­quent­ly for every­thing from “seri­ous dis­cus­sions of race rela­tions in the U.S. to play­ful con­fronta­tions aimed at pro­mot­ing fights.” Cavett’s show “pro­vid­ed a com­fort zone for Ali, espe­cial­ly before he became a beloved fig­ure.” And it gave Ali a forum to counter pub­lic slan­der. In the clip above from 1970, he talks about how his sac­ri­fices made him a cred­i­ble role mod­el for trou­bled young peo­ple.

He seems at first to com­pare him­self to ear­ly Amer­i­can pio­neers, Japan­ese kamikaze pilots, and the first astro­nauts when Cavett asks him about the pos­si­bil­i­ty of going to jail, but his point is that he thinks he’s pay­ing a small price com­pared to what oth­ers have giv­en up for progress — “We’ve been in jail 400 years,” he says. “The sys­tem is built on war.” The fol­low­ing year, the Supreme Court would dis­miss the case against him, swayed by the argu­ment that Ali opposed all war, not just the war in Viet­nam. He saw Cavett as a wor­thy spar­ring part­ner, help­ing the late-night host earn a place on Nixon’s list of ene­mies. It would become a place of hon­or in the com­ing years as Ali won back his career, his rep­u­ta­tion, and his title in the “Rum­ble in the Jun­gle” four years lat­er, and the Viet­nam War became a cause for nation­al shame.

Relat­ed Con­tent: 

Muham­mad Ali Gives a Dra­mat­ic Read­ing of His Poem on the Atti­ca Prison Upris­ing

“Muham­mad Ali, This Is Your Life!”: Cel­e­brate Ali’s Life & Times with This Touch­ing 1978 TV Trib­ute

When Jack John­son, the First Black Heavy­weight Cham­pi­on, Defeat­ed Jim Jef­fries & the Footage Was Banned Around the World (1910)

Josh Jones is a writer and musi­cian based in Durham, NC. Fol­low him at @jdmagness