(CNN) - Former President Bill Clinton called on Howard University's class of 2013 to create a world that does not leave behind individuals like the two young men accused of bombing the Boston Marathon last month.
"They were not as empowered as you were," he said at Saturday's commencement ceremonies.
"Two boys come here looking for a college education, seem to be doing well, then this or that or the other thing happens," and their lives took a dramatic turn, Clinton said.
Dzhokhar Tsarnaev, 19, was a student at the University of Massachusetts-Dartmouth and his 26-year-old brother Tamerlan, who died after a shootout with police days after the bombing, attended a community college between 2006 and 2008.
Clinton pointed to the Tsarnaev brothers and Faisal Shahzad, who graduated from the University of Bridgeport before launching his failed attempt to bomb Times Square, as examples of immigrants who were isolated and lashed out against others.
"Perhaps we'll never fully understand" what motivated them, he said, but he called for graduates at the historically black college in Washington to improve the world.
"You can't share the future unless you share the responsibility for building it, and I implore you to look for opportunities to do that," he said.
As an example of overcoming differences, Clinton cited the once-unlikely alliance his wife, former Secretary of State Hillary Clinton, formed with President Barack Obama after their 2008 bids for the White House.
“They fought this huge campaign tooth and nail, a trench campaign down to the end,” Clinton said. “He (Obama) was big enough to ask her to be secretary of State. She was big enough to take it. They trusted each other, and they both acknowledged that the differences in their positions were not that profound.”