Marx and, more specifically, Lenin thought communist politicians should do two things (and stressed the necessity of this in party work). Firstly they should use their position in the state to obstruct the bourgeois' war on the international working class. Secondly they should use their platform to agitate the proletariat into action. Regardless of how seemingly infeasible a general strike is, a politician calling for one is actually agitating the proletariat, calling for the proletariat's direct intervention in politics with one of their most potent weapons. Contrast this with any other social-democratic politician who might pay lip service to the labor movement or unions but ultimately desires the proletariat's political activity be constrained to voting while matters are sorted out in the halls of bourgeois power.