Parallelism means using similar grammatical structures to emphasize related ideas. Parallel structure may involve a single word, a phrase, a clause, a full sentence, or even a series of paragraphs.

In his speech to mark the fiftieth anniversary of the civil rights march in Selma, Alabama, President Barack Obama uses parallel structure to stress the unity of a diverse nation. Toward the end of his speech, he exhorts, “Look at our history.” He then goes through various people that mark our nation’s history:

We are Lewis and Clark and Sacajawea, pioneers who braved the unfamiliar, followed by a stampede of farmers and miners, and entrepreneurs and hucksters. [. . .]

We are Sojourner Truth and Fannie Lou Hamer. [. . .]

We’re the immigrants who stowed away on ships to reach these shores, the huddled masses yearning to breathe free—Holocaust survivors, Soviet defectors, the Lost Boys of Sudan. [. . .]

We’re the slaves who built the White House. [. . .] We’re the ranch hands and cowboys. [. . .]

We’re the fresh-faced GIs who fought to liberate a continent. And we’re the Tuskeegee Airmen, and the Navajo code-talkers, and the Japanese Americans who fought for this country even as their own liberty had been denied.

We’re the firefighters who rushed into those buildings on 9/11, the volunteers who signed up to fight in Afghanistan and Iraq. [. . .]

We are storytellers, writers, poets, artists who abhor unfairness, and despise hypocrisy, and give voice to the voiceless, and tell truths that need to be told.

We’re the inventors of gospel and jazz and blues, bluegrass and country, and hip-hop and rock and roll, and our very own sound with all the sweet sorrow and reckless joy of freedom.

After this catalog of all the different people and voices who make up this country, Obama concludes, “That’s what America is.” The similar structure at the beginning of each sentence, along with the different endings, allows for differences while stressing the likenesses that Obama claims are the hallmark of the United States.