Other social democrats however were more convinced than Hyndman of the utility of Trade Union action. Trade unionism is criticised by those of council communist and left communist tendencies. Here, trade unionism is seen as being more useful to capitalists than to workers, and as a kind of "safety-valve" that helps to keep working-class discontent within reformist channels and prevent it from evolving into revolutionary action. They consider a global state composed of workers' councils to be the ultimate union to which all workers in the world belong; unions that organize based on trade further divide the working class and act as a mechanism to allow the working class to vent concerns without actually uniting and becoming revolutionary. In contrast to other left critiques of trade unionism, these tendencies do not accept that the problems they identify could be remedied by changing the structure, leadership or objectives of trade unions. They argue that trade unionism is inherently reformist because it is sectarian and is not founded in the workplace itself and that revolutionary action is possible only if workers act outside trade unionism through workers' councils or other channels. There is also a philosophical difference between the craft unionism of many AFL-type unions, and the industrial unionism of organizations such as the Industrial Workers of the World. Industrial unionists decry a practice that they call "union scabbing," in which craft unionists are required by the no-strike clause in their contracts to cross the picket lines of other unions. There is also the left critique of the tendencies of some labor unions to become bureaucratic and for the union leaders and staff to become detached from the needs and interests of the rank and file union members, in contrast to the practices of union democracy. The Labor Notes, in the United States, is an example of an organization that attempts to fight this bureaucratic tendency. Violence: