When John F. Kennedy asked young Americans in 1960 how many of them were willing to spend years in the developing world “working for freedom,” he surely had people like Marjorie Michelmore in mind. What he couldn’t have anticipated is how the young Marjorie almost sent his whole vision for the Peace Corps up in smoke....

The idea [of the Peace Corps] attracted its share of critics who questioned the idealism of the concept and the capacity of young people to conduct the hard work of development and diplomacy. Kennedy’s presidential opponent, Richard Nixon, condemned it as a potential “haven for draft dodgers,” according to a 1960 article from the Harvard Crimson. And the cadre of professional diplomats in America’s foreign service had their misgivings as well.

Which explains why a postcard Michelmore wrote to her boyfriend from her Peace Corps teacher training at the University of Ibadan in Nigeria became such a flash point. America may have been transitioning, but think what Nigeria was experiencing — as a new nation just granted independence from Britain the previous October. It was part of a huge swath of the African continent casting off colonial rule and testing new forms of government and self-empowerment.

So imagine Nigerians’ embarrassment at what Michelmore wrote on the postcard, which she accidentally dropped before mailing. It landed in the hands of a Nigerian student and then on the front pages of the country’s newspapers — and later the world’s. “We really were not prepared for the squalor and absolutely primitive living conditions,” she wrote, noting how she’d “had no idea what ‘underdeveloped’ meant.” She went on to say that it’d been “a very rewarding experience,” but the damage was done. For Nigerians, so proud of their new country, the “word ‘primitive’ was as insulting as anything anybody could say,” says Hoffman. Students launched protests that turned into riots. A distraught Michelmore had to flee the country. “I possibly thought I might have wrecked the whole Peace Corps idea,” she later recalled in Smith’s alumni magazine.

In the end, of course, the Peace Corps survived, not the least because of the grace and perseverance of Michelmore, her colleagues, their Nigerian hosts and Kennedy himself. When Nigerians demanded the program be expelled from their country, another American volunteer “went on a modified hunger strike,” Hoffman says, refusing to eat unless he could dine with the Ibadan students. At a time when parts of the United States — including Washington, D.C. — were still racially segregated, that kind of gesture resonated. Michelmore apologized to Nigeria’s leader before leaving the country, and on her way home she received a cable from Kennedy thanking her for her “steadfastness” in the face of turmoil. “We are strongly behind you and hope that you will continue to serve in the Peace Corps.” She did, working for the program in D.C. the following year. ...