[2] His activism included supporting the FARC rebels in the Colombian civil war; campaigning against the Turkish Occupation of Cyprus, and supporting the recognition of the Armenian and Greek genocides, he supported the creation of a Kurdish state in the Kurdish conflict in Turkey, and called for the cessation of The Troubles, against neoliberalism and also against the authoritarian governments of the Arab States.

[1] In the 2004, Mac Manus became a leading member of Foreningen Oprør [da] ("Rebellion"), a pro-Communist organisation.

In August 2005, due to his activity on behalf of Foreningen Oprør, Mac Manus was arrested by Danish police and questioned about attempting to provide financial aid to a number of groups on EU's list of banned terrorist organisations, which included FARC, Euskadi Ta Askatasuna and the Popular Front for the Liberation of Palestine (PFLP).

[3] In 2008 the Columbian Minister of Justice called upon the Danish government to extradite Mac Manus to Columbia to stand trial.

[4] On 15 March 2010 Mac Manus was sentenced to 6 months' probation in Denmark for attempting to violate section 114b of the Criminal Code on support for terrorist organizations by soliciting financial support for FARC and PFLP.