On June 8, 1968, the most dramatic display of public grief for an American who had never been elected to the presidency unfolded as a twenty-one-car train, its engine draped in black, carried 1100 mourners and the body of senator Robert F. Kennedy from his funeral in New York to his burial in Arlington National Cemetery. Crowds had been expected, but no one had imagined that on a steamy June Saturday two million people would suddenly head for the tracks, filling tenement balconies and clambering onto factory roofs, waving hand-lettered GOODBYE BOBBY signs, forging a 226-mile-long chain of grief and despair.

The train traveled so slowly that its passengers, who included numerous political, media, and Hollywood celebrities, could look outside and see their grief reflected in the faces of people they usually flew over or sped past. They saw black Americans weeping, kneeling, and holding up children, and they saw policemen in dress uniforms and veterans in overseas caps snapping salutes--white working-class voters who had decided that the most fitting way to mourn a politician who had condemned the war in Vietnam as “deeply wrong,” was to wear a uniform and wave a flag. Life correspondent Sylvia Wright saw a wedding party standing in a Delaware meadow. The bridesmaids held the hems of their dresses in one hand and their bouquets in the other. As the car carrying Kennedy’s coffin passed, they tossed their flowers against its side. After seeing this, and the solemn Boy Scouts and the brawny white men gripping tiny flags as tears rolled down their cheeks, Wright asked herself the question that has become the silent descant of much that has been written or said about Robert Kennedy: “What did he have that he could do this to people?”

The most obvious answer is that he was the oldest surviving brother of a beloved and martyred president. But even this, and even his youth, eloquence, and good looks are not enough to explain the intensity and longevity of the grief. Had he been assassinated before launching his campaign on March 16, it is inconceivable that two million people would have turned out for his funeral train, or that his phantom presidency would remain as haunting. This means that the answer to Wright’s question can be found in his campaign.

In a word, Kennedy had courage.

His physical courage was obvious: he traveled with one unarmed bodyguard, rode in open cars (as his brother had in Dallas), and plunged into crowds heedless of the dangers he was courting by becoming the second Kennedy in a decade to run for president. During a 1966 speech to students in South Africa, Kennedy had described moral courage as “a rarer commodity than bravery in battle or great intelligence,” extolling it as “the one essential, vital quality of those who seek to change a world which yields most painfully to change.” It was this kind of courage that made his campaign so unusual and moving.

He showed moral courage by constantly criticizing and challenging his audiences, even friendly ones. Because he believed that Americans had an equal responsibility to participate in their nation’s political life and fight its wars, he repeatedly told students that he opposed the draft deferments that saved them from fighting and dying in Vietnam, and whenever he did this applause gave way to boos and catcalls. Because he believed that “shared ideals and purposes,” rather than “income and homes” made a nation great, he attacked one of the sacrosanct tenets of American political discourse, that economic growth, consumption and the American Dream were inextricably linked, telling audiences that “we seem to have surrendered community excellence and community values in the mere accumulation of material things.”

It took moral courage to tell Americans that they were individually responsible for what their government had done in their name in Vietnam, and had failed to do at home for minorities and the poor. In one of his last speeches in the Senate he said, “It is we who live in abundance and send our young men out to die. It is our chemicals that scorch the children and our bombs that level the villages. We are all participants.” And it took moral courage to accept his own responsibility for Vietnam. One of the television spots that he ran in Indiana showed him telling a group of war veterans, “The administration with which I was intimately associated is also going to have to share the responsibility when blame is assessed–not just the administration, but me personally.”

It was also courageous to insist that Americans could not acquit themselves of their moral responsibilities simply by voting for a new president and new policies. Instead, he said, they would have to help heal the national soul by working to end hunger, discrimination, and poverty. When students at Valparaiso University in Indiana assailed him for advocating the use of federal funds to fight poverty, he shot back, “How many of you spent time over the summer, or on vacations, working in a black ghetto, or in eastern Kentucky, or on Indian reservations? Instead of asking what the federal government is doing about starving children, I say, what is your responsibility?”

After traveling with Kennedy for several weeks, speechwriter John Bartlow Martin noted that, “He went yammering around Indiana about the poor whites of Appalachia and the starving Indians who committed suicide on the reservations and the jobless Negroes in the distant great cities, and half the Hoosiers didn’t have any idea what he was talking about, but he plodded ahead stubbornly, making them listen, maybe even making some of them care, by the sheer power of his own caring.” But why keep hammering away at the plight of the poor in a conservative state like Indiana where there was more chance for political loss then gain? Kennedy told a reporter that he put up with all the banalities and indignities of campaigning because, “For every two or three days that you waste time making speeches at rallies full of noise and balloons there’s usually a chance . . . to teach people something . . . to take them some place vicariously that they haven’t been, to show them a ghetto, or an Indian reservation.” It was moments like these, he said, that made a presidential campaign “worth it.”

Kennedy’s moral courage was also evident in the things that he refused to do. He never pandered to his audiences or spoke down to them; he quoted Camus, Emerson, and Sophocles to inner city minorities, farmers, and college students alike. He never trumpeted his religious faith, and aide Jeff Greenfield remembers him mentioning God only once, when he said, “The only person who can solve our problems is God, and she isn’t running this year.” He never questioned his opponents’ character or patriotism, perhaps because he understood that it would be difficult to follow a crude and divisive campaign with a high-minded presidency would be difficult, and healing a morally wounded nation after running an immoral campaign would be impossible.

His courageous campaign has left us with a template for how a candidate should run for the White House at a time of moral crisis, and for how, as he put it, “the people themselves can lead the way back to those ideals which are the source of national strength and generosity and compassion of deed.”