The former CIA boss also commented on a broad range of other topics at the London summit. He demanded “immigration reform,” for example, perhaps linked to what he termed the “unique” demographics of the three NAFTA countries. Turning to Iraq and the escalating crisis there, Petraeus also cautioned against air strikes without a more coherent strategy. “The United States cannot be the air force for the Shia militias,” he said. Separately, he claimed that Washington, D.C., politics was the biggest threat to U.S. national security.