President Trump tweeted on August 22 that he has directed Secretary of State Mike Pompeo to “closely study the South Africa land and farm seizures” and the “large scale killing of farmers.” In his tweet, the president quoted Fox News host Tucker Carlson that “South African government is now seizing land from white farmers.”

“Presidential Policy Directive/PPD-28: Signals Intelligence Activities,” White House, January 17, 2014. When the United States collects nonpublicly available signals intelligence in bulk, it shall u…