President Donald Trump just revealed how unseriously he takes national security. During a joint press conference Tuesday with Turkish President Recep Tayyip Erdoğan in Ankara, Trump appeared dumbfounded when pressed about his terms for potentially selling F-35 fighter jets to Turkey despite a congressional ban. A reporter asked Trump whether the sale of F-35 jets would require the country’s Russian-made S-400 missile defense system to be sold to a “third party.” “Third party? What is the third