In third grade, Barack Obama wrote an essay titled, “I Want to Become President”—and he is, to this day, determined to show the world that, yes, he can. Born in the U.S.A., the son of an African father and an American mother, a boy who spent his childhood in Indonesia and Hawaii, Barack Obama is truly a citizen of the world. His campaign for the presidency is powered by a fierce optimism, an exuberant sense of purpose and determination, and, above all, a belief that change can happen.

Garen Thomas takes …