Tt was the CIA that infiltrated the communists in Italy for the exact purpose of shaping the politics of the continent to their design.
https://en.wikipedia.org/wiki/CIA_activities_in_Italy
See also:
https://moderndiplomacy.eu/2020/11/13/how-the-cia-created-th...
You may think that this accordance of like-mind was spontaneous, but it has clearly been a half-century long project of the United States.
No wonder their disappointment when their main man inside the bloc, the UK, elected to leave.