Because of the notion of the withering away of the state after the dictatorship of the proletariat, and the consequent difficulty in defining nationhood, communist countries have been reluctant to join international organizations or recognize or abide by international conventions. However, the communist movement has always asserted its 'proletarian international' basis. Cold war tactics of international relations have been frequently used by communist countries with respect to capitalist countries and with respect to each other. Political, military and trade agreements are concluded within the communist system. Trade agreements are also made with capitalist countries. But on certain issues non-recognition of international law and conventions serves to increase international tension and uncertainty. Where communist countries are members of important international organizations, they may use veto or other methods of blocking the policies of capitalist nations or the smooth running of the organizations.