Hours after a deadly terror attack in Barcelona, President Donald Trump suggested that Islamic terrorists should be executed with bullets soaked in pig’s blood, praising a discredited story of a 20th-century atrocity. “Study what General Pershing of the United States did to terrorists when caught,” Trump tweeted Thursday afternoon. “There was no more Radical Islamic Terror for 35 years!” The tweet referenced a false story that Trump told at rallies more than once on the campaign trail.