What is the battle of the bourgeoisie?

From the text:

The bourgeoisie finds itself involved in a constant battle. At first with the aristocracy; later on, with those portions of the bourgeoisie itself, whose interests have become antagonistic to the progress of industry; at all time with the bourgeoisie of foreign countries. In all these battles, it sees itself compelled to appeal to the proletariat, to ask for help, and thus, to drag it into the political arena. The bourgeoisie itself, therefore, supplies the proletariat with its own elements of political and general education, in other words, it furnishes the proletariat with weapons for fighting the bourgeoisie.