President Barack Obama delivers a speech to the African Union in Addis Ababa, Ethiopia, on Tuesday, July 28. Obama is the first American leader to visit Ethiopia, Africa's second-most populous nation. The visit follows a brief trip to Kenya, Obama's first visit to his father's homeland as commander in chief. Evan Vucci/AP
Dr. Nkosazana Dlamini-Zuma, right, chairwoman of the African Union Commission, stands with Obama as he looks up at the crowd before delivering a speech to the African Union on July 28. Evan Vucci/AP
Obama talks with farmer Gifty Jemal Hussein, second from right, about her corn during a tour of Faffa Food in Addis Ababa on July 28. Evan Vucci/AP
Obama stands alongside workers at Faffa Food as they pack boxes of food products in Addis Ababa on July 28. Faffa Food produces low-cost and high-protein foods. SAUL LOEB/AFP/Getty Images
Obama and Ethiopian Prime Minister Hailemariam Desalegn are waited on during a state dinner Monday, July 27, at the National Palace in Addis Ababa. Evan Vucci/AP
Desalegn, right, watches as Obama touches the "Lucy" exhibit at the National Palace on July 27. "Lucy" is made up of several hundred pieces of bone representing 40% of a female Australopithecus afarensis, a human-like species estimated to have lived in Ethiopia 3.2 million years ago. Evan Vucci/AP
Obama speaks during a joint news conference with Desalegn at the National Palace on July 27. Evan Vucci/AP
Obama and Desalegn review an honor guard at the National Palace on July 27. Sayyid Azim/AP
Obama speaks on South Sudan and counterterrorism issues during a multilateral meeting with Kenya, Sudan, Ethiopia, the African Union and Uganda on July 27. Evan Vucci/AP
Security stands guard as Obama's motorcade drives to the National Palace in Addis Ababa on July 27. SAUL LOEB/AFP/Getty Images
Obama receives flowers Sunday, July 26, upon his arrival at Bole International Airport in Addis Ababa. SAUL LOEB/AFP/Getty Images
Obama boards Air Force One as he prepares to depart Jomo Kenyatta International Airport in Nairobi, Kenya, on Sunday, July 26. SAUL LOEB/AFP/Getty Images
Obama talks with Kenyan President Uhuru Kenyatta in front of Marine One in Nairobi on July 26. The U.S. President called on Kenya's leaders to reject ethnic divisions and government corruption. SAUL LOEB/AFP/Getty Images
Obama addresses representatives of civil society organizations at the Young African Leaders Initiative Regional Leadership Center in Nairobi on July 26. SAUL LOEB/AFP/Getty Images
Obama speaks at the Moi International Sports Center in Nairobi on July 26. He offered his own personal history as evidence that all Africans have the potential to rise from even the most difficult circumstances. CARL DE SOUZA/AFP/Getty Images
Obama embraces his half-sister Auma Obama during an event at the Moi International Sports Center on July 26. She introduced Obama to the crowd, saying her brother "continues to be very attached to us." The President spent portions of each night in Kenya with relatives. SAUL LOEB/AFP/Getty Images
Kenyans wave to members of Kenya's Parliament as they wait for Obama's arrival on July 26. Georgina Goodwin/AFP/Getty Images
Obama and national security adviser Susan Rice share a toast during a state dinner in Nairobi on Saturday, July 25. SAUL LOEB/AFP/Getty Images
Obama's step-grandmother, Mama Sarah, attends the state dinner in Nairobi on July 25. SAUL LOEB/AFP/Getty Images
Obama speaks during a news conference with Kenyatta on July 25. Evan Vucci/AP
A security guard blocks a Nairobi street as Obama's motorcade passes on July 25. Ivan Lieman/AFP/Getty Images
Crowds gather near Memorial Park in Nairobi to cheer Obama's motorcade on July 25. Ivan Lieman/AFP/Getty Images
Obama speaks during a meeting with Kenyatta (not pictured) at the State House in Nairobi on July 25. SAUL LOEB/AFP/Getty Images
Obama pays his respects after laying a wreath at the Memorial Park in Nairobi on July 25. The park commemorates the 1998 truck bombing of the U.S. Embassy there, which killed a dozen Americans and more than 200 Kenyans. Almost simultaneously, 11 people were killed in a similar attack on the U.S. Embassy in Tanzania's capital. SAUL LOEB/AFP/Getty Images
Obama talks with Michael Wanyonyi, CEO and founder of Mibawa Suppliers, on July 25 as he visits the Power Africa Innovation Fair, an initiative to increase the number of people with access to electricity in sub-Saharan Africa. SAUL LOEB/AFP/Getty Images)
Obama and Kenyatta wave July 25 as they leave the Global Entrepreneurship Summit at the United Nations Compound in Nairobi. Evan Vucci/AP
Obama and Kenyatta attend a panel discussion at the Global Entrepreneurship Summit. From left are Obama; Judith Owegar, co-founder of Akirachix; Kenyatta; Josipa Majic, CEO of Teddy the Guardian; and Jahiel Oliver, CEO of Hello Tractor. SAUL LOEB/AFP/Getty Images
Obama inspects a guard of honor at the State House in Nairobi on July 25. SIMON MAINA/AFP/Getty Images
Obama arrives for the Global Entrepreneurship Summit. SAUL LOEB/AFP/Getty Images
Obama signs a guest book alongside Kenyatta upon arrival at Kenyatta International Airport in Nairobi on Friday, July 24. SAUL LOEB/AFP/Getty Images
Obama greets Kenyatta on July 24. Tom Maruko/Pacific Press/LightRocket/Getty Images
Kenyatta watches as Obama hugs his half-sister Auma on July 24. Evan Vucci/AP
Obama hugs Joan Wamaitha, 8, upon his arrival in Kenya on July 24. SAUL LOEB/AFP/Getty Images
Obama waves from the door of Air Force One after arriving in Kenya on July 24. SAUL LOEB/AFP/Getty Images