World revolution is the Marxist concept of overthrowing capitalism in all countries through the conscious revolutionary action of the organized working class. For theorists, these revolutions will not necessarily occur simultaneously, but where and when local conditions allow a revolutionary party to successfully replace bourgeois ownership and rule, and install a workers' state based on social ownership of the means of production. In most Marxist schools, such as Trotskyism and Communist Left, the essentially international character of the class struggle and the necessity of global scope are critical elements and a chief explanation of the failure of socialism in one country.