https:// russia-insider.com/en/politics/trump-threatens-eliminate-columns-historic-speech-cia-video/ri18655
https:// en.wikipedia.org/wiki/Fifth_column
>A fifth column is any group of people who undermine a larger group from within, usually in favor of an enemy group or nation
>During the Siege of Madrid in the Spanish Civil War, Nationalist general Emilio Mola told a journalist in 1936 that as his four columns of troops approached Madrid, a "fifth column" (Spanish: Quinta columna) of supporters inside the city would support him and undermine the Republican government from within.