For President Obama, the inauguration on Jan. 21 will be one of innumerable moments in the spotlight, albeit a significant one. But for the official inaugural poet — for poetry itself — it will be a singular event: Tens of millions of people all over the world will listen. In unison. To a poem. For many, it will be the only poem they hear for four years.

On Wednesday, the Presidential Inaugural Committee announced that Richard Blanco had been chosen to speak at the swearing-in ceremony. The author of three critically acclaimed collections, Blanco is a relatively obscure writer, even in the world of poetry, where giants are often unknown to the public at large. In the announcement, his superlative personal story attracted more attention than his work: Blanco, 44, will be the youngest poet, the first Hispanic poet and the first gay poet to speak at an inauguration.

Blanco’s appointment raises questions about the purpose of the inaugural poet, a tradition with much shorter roots in the United States than in England, where poet laureates have been commemorating acts of state for hundreds of years. Blanco will be just the fifth poet to speak at a presidential inauguration, following Robert Frost (1961), Maya Angelou (1993), Miller ­Williams (1997) and Elizabeth Alexander (2009).

Jonathan Galassi, a distinguished poet and the president of the publishing company Farrar, Straus & Giroux, points out that the tradition of what’s called “occasional poetry” — poetry written for a specific occasion — has ancient roots. “Think about Horace,” he said from his office in New York. “He wrote great occasional poems for Augustus. And you could say that ‘The Aeneid’ is a public poem: It’s about the founding of Rome. It’s a political statement. And there are other great poems that were inspired by political moments.”

Poet Mary Karr acknowledges that “many poets are skeptical of an inauguration poem, but I’m not.” Speaking from her home in Upstate New York, she said: “Any forum that puts a poet on the national stage with the presumption that that person is going to be relevant and interesting, that’s a good thing. And I love the idea of an immigrant at a time like this. Does it politicize the position? Yes, but it doesn’t hurt poetry.”

Richard Blanco. Blanco, 44, the son of Cuban exiles, is the 2013 inaugural poet, joining the ranks of Maya Angelou and Robert Frost. (Nikki Moustaki/AP)

But everyone acknowledges the risks involved. Contemporary poetry tends to be lyrical and personal. Art associated with political parties or politicians carries a whiff of propaganda.

The danger Galassi sees is that occasional poetry “can become empty and wooden. I’m not a great lover of official poetry, but I do think the idea that poetry is used in the inauguration to emphasize certain values is politically and culturally significant.”

“It’s such a tough assignment,” said Deborah Garrison, the poetry editor at Knopf. “You’re being asked to speak for a nation. You have to find a way to make it every person’s story. How do you get to the big issues, the big themes?”

The immensity of the task and the inauguration itself — spread across the whole Mall — poses its own unique challenges for any poet.

Garrison Keillor, whose “Writer’s Almanac” brings ­poetry every weekday to listeners of public radio, said in an e-mail, “This is one honor that should be politely declined. The poor poet steps out on stage in the midst of all that pomp and the vast crowd is restless and the poem drops (plink) like a small stone in a big lake and everyone thinks, ‘That’s it?’ Robert Frost made a good show of it, and everyone since then has been a clinker.”

But Don Share, senior editor of Poetry Magazine, applauds the president’s choice. Speaking from his office in Chicago, he said that Blanco’s poems “sound like so many people in this country. He works in Spanish and English, a mixture that is our native language, and he makes it sounds like real poetry. This is poetry that speaks for and from a great number of Americans. He gives a voice to the kinds of experience that people undergo every single day. Even people who don’t want to read it themselves can understand the value of a moment in which we say that this country is made of poetry.”