 Complete the following phrase:  In 2000, a Parliament Commission report from the left-wing coalition Gruppo Democratici di Sinistra lUlivo asserted that a strategy of tension had been supported by the United States to stop the PCI, and to a certain degree also the PSI, from reaching executive power in the country. It stated that Those massacres, those bombs, those military actions had been organized or promoted or supported by men inside Italian state institutions and, as has been discovered more recently, by men linked to the structures of United States intelligence. The report stated that US intelligence agents were informed in advance about several rightwing terrorist bombings, including the December 1969 Piazza Fontana bombing in Milan and the 