President Obama used rap — complete with some impromptu beatboxing — to make an important point about self-expression this week. While visiting Vietnam, Obama spoke about free speech, as officials in the country have recently tried to crack down on social media posts. During a town hall meeting Wednesday, he invited Vietnamese rapper Suboi to share a few freestyle lines, which he used as a segue into his own commentary. Before Suboi shared her rap, Obama beatboxed to get the flow started. Suboi, who rapped in Vietnamese, said her verses were about the wealthy, suggesting that they aren't "really happy." She also mentioned that people hold stereotypes about female rappers. "There's always been sexism and gender stereotypes in the music industry, like every other part of life," Obama said at the town hall, in response to Suboi. "Now, I feel closer to something like rap, which started off as an expression of poor African-Americans, now suddenly has become a global phenomenon, and is really the art form of most young people today around the world in a lot of ways." The president went on to use the musical analogy to make a larger statement about free speech. "Imagine if, at the time when rap was starting off, that our government had said, 'No. Because some of the things you say are offensive,' or, 'Some of the lyrics are rude,' or, 'You're cursing too much,'" Obama said. "That connection that we've seen now in hip-hop culture around the world wouldn't exist. So, you've got to let people express themselves. That's part of what a modern, 21st-century culture is all about." You can watch the video below.