James Mattis, U.S. Secretary of Defense, and Kirstjen Nielsen, U.S. Secretary of Homeland Security, answer questions from U.S. soldiers at Base Camp Donna in Donna, Texas, November 14, 2018. The military announced in late October that over 7,000...more

James Mattis, U.S. Secretary of Defense, and Kirstjen Nielsen, U.S. Secretary of Homeland Security, answer questions from U.S. soldiers at Base Camp Donna in Donna, Texas, November 14, 2018. The military announced in late October that over 7,000 troops would go to the border with Mexico as a caravan of Central American migrants slowly heads toward the United States. Master Sgt. Jacob Caldwel/U.S. Army/Handout via REUTERS

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