"Reds under the bed"

Origin of the term
 According to en.wiktionary.org- 
 * From red (meaning communist) and the traditional child's fear of a monster lurking under the bed.


 * Noun- Red under the bed (plural reds under the bed).


 * (slang) An insidious communist presence; a communist who has infiltrated capitalist society.

Political slur
It was used as a way of smearing non revolutionary and non-communist left-wingers during the Cold War.

Also see

 * 1) Cold War
 * 2) Organisations
 * 3) Threat construction
 * 4) Terrorist organisations
 * 5) Red Brigades (in Italy)
 * 6) Politically Communist and/or Socialist
 * 7) House Committee on Un-American Activities