"The Communists are distinguished from the other working-class parties by this only:
-
In the national struggles of the proletarians of the different countries, they point out and bring to the front the common interests of the entire proletariat, independently of all nationality
-
In the various stages of development which the struggle of the working class against the bourgeoisie has to pass through, they always and everywhere represent the interests of the movement as a whole."
(https://www.marxists.org/archive/marx/works/1848/communist-manifesto/ch02.htm)