A three-day summit that included the leaders of 49 nations on the African continent concluded Thursday in Washington. It was the first such gathering in eight years and included pledges of significant new involvement by the United States. White House Correspondent Laura Barrón-López reports. Stream your PBS favorites with the PBS app: https://to.pbs.org/2Jb8twG Find more from PBS NewsHour at https://www.pbs.org/newshour Subscribe to our YouTube channel: https://bit.ly/2HfsCD6 Follow us: Facebook: http://www.pbs.org/newshour Twitter: http://www.twitter.com/newshour Instagram: http://www.instagram.com/newshour Subscribe: PBS NewsHour podcasts: https://www.pbs.org/newshour/podcasts Newsletters: https://www.pbs.org/newshour/subscribe