After 155 years, Juneteenth, a celebration of the emancipation of enslaved Americans, is being acknowledged as a holiday by corporations and state governments across the country. Today, we consider why, throughout its history, Juneteenth has gained prominence at moments of pain in the struggle for black liberation in America. We also ask: What does freedom mean now? Guest: Dr. Daina Ramey Berry, a professor of history at the University of Texas at Austin. For more information on today’s episode, visit nytimes.com/thedaily  Background reading: In a project examining the history and import of Juneteenth, we ask: What is freedom in America?Opal Lee, 93, an activist and lifelong Texan, has campaigned to make June 19 a national holiday for years. This is her vision for honoring the emancipation of enslaved Americans.