A '''fifth column''' is a group of people or sympathizers who rationally and clandestinely try to undermine a larger group to which it is expected to be loyal. Members may engage in espionage or sabotage within defense lines or within national borders.
The expression dates from the [[Spanish Civil War]] in 1936 when the Francoist General Mola, whose forces were threatening Madrid, boasted that he had four columns approaching the city and a fifth column within it.
During the [[Second World War]], when British citizens were anxious about supposed fifth-columnists in the UK, the artist [[William Heath-Robinson]] produced a series of cartoons about the Sixth Column, patriotic men and women devoted to frustrating the actions of the Fifth Column.<ref>http://www.liverpoolmuseums.org.uk/walker/exhibitions/heathrobinson/Sixth_column.asp</ref> There was also a reference to existence of a Nazi or Hitler Fifth Column being in existence during WWII.<ref> David Vaughan, Hitler's Fifth Column", https://www.radio.cz/en/section/talking/hitlers-fifth-column, December 2, 2002</ref><ref>Claire Ellicot | ''The Daily Mail'', Spy who tricked me: Nazi agents in secret ‘fifth column’ group were fooled by MI5 using fake medals and made-up Gestapo boss called ‘Jack King’ https://www.dailymail.co.uk/news/article-6149475/Nazi-agents-secret-fifth-column-group-fooled-MI5-using-fake-medals.html, SSeptember 9, 2018</ref>
In the United States, the [[Democratic Party]] has been considered America’s Communist Fifth Column,
which is promoting [[Socialism]]. It emerged from deep within the U.S. government itself and has reached the point where, as reported in June 2017, even the mention of God and country are topics which trigger microaggressions. The Communist Party USA’s national chairman John Bachtell acknowledged that the Democratic Party is its greatest ally, and is bent on destroying America from within its own infrastructure. ''Accuracy in Media'' has reported that "Since 1988, the CPUSA has not run its own candidates for president and vice-president, preferring instead to work through the Democratic Party." In 2012, economist [[Peter Schiff]], found that the majority of individuals within the Democratic National Convention’s delegation were enthusiastic supporters of outlawing profitability. As discussed in the cited article, the gravest threat to America's democracy is the Democrat Fifth Column.<ref> Jonathan P. Henderson | THE CONSERVATIVE HISTORICAL REVIEW , The Democratic Party: America’s Communist Fifth Column, https://theconservativehistoricalreview.wordpress.com/2017/06/24/the-democratic-party-americas-communist-fifth-column/, 24 Jun 2017 </ref>