Esper was asked by a reporter in Germany about criticism from members of Congress, including Rep. Mac Thornberry (R-Texas) who called the diversion of funds contrary to the constitutional authority of Congress.
“Border security is national security,” Esper said, “and national security is our mission.”
He added, “The action we took is legal under the law, and so it should be no surprise, and I'll just leave it at that for now.”
Esper spoke on the sidelines of an international security conference in Munich.
The Pentagon said Thursday that it authorized $3.8 billion to be diverted toward building some 177 miles of barrier across the U.S.-Mexico border, in an effort to address drug-smuggling activities.
“DHS has identified areas along the southern border of the United States that are being used by individuals, groups, and transnational criminal organizations as drug smuggling corridors, and determined that the construction of additional physical barriers and roads in the vicinity of the United States border is necessary in order to impede and deny drug smuggling activities,” acting Department of Defense comptroller Elaine McCusker said in a request sent to Congress.
The request seeks a $2.2 billion diversion from defense appropriations and $1.63 billion from the Pentagon’s Overseas Contingency Operations fund, which supports operations against the ISIS terrorist group.
Diverting money from the defense appropriations would affect funding for two F-35 fighters, eight Reaper drones, four Air Force C-130 transport aircraft, two Marine V-22 Osprey helicopters, amphibious ships, National Guard equipment, and Army trucks.
The construction of a border wall along the southwest border has been a key promise of President Donald Trump and one he is adamant in fulfilling. The administration has diverted funds from the Pentagon before for wall infrastructure between the United States and Mexico.
The “southwest border is a security issue, and so we’ll see how things play out, but we remain committed to supporting the Department of Homeland Security in its mission,” he said, adding that the support could include financial support.