A new study from the Migration Policy Institute documents a shocking amount of money being devoted to keeping immigrants out of the U.S. How much money?

The U.S. government spends more on federal immigration enforcement than on all other principal federal criminal law enforcement agencies combined, with the nearly $18 billion spent in fiscal 2012 approximately 24 percent higher than collective spending for the FBI, Drug Enforcement Administration, Secret Service, U.S. Marshals Service and Bureau of Alcohol, Tobacco, Firearms and Explosives.