Was internationalism a grand failure? Was it practiced even bt those who proclaimed it? Beyond the international congresses with their affirmations of working-class solidarity, the meaning of internationalism seems to unravel. Marx called for international solidarity precisely because socialist activists operated, conceptually and practically, within a world of nationstates. Modern nationalism and the internationalism of workers's movements at best can be considered “twins, developing side by side in an uneasy relationship since 1830s”. While an international economy and division of labor surely existed before World War I, workers' internationalism seemed more a rhetorical response to modern nationalism than a pragmatic response to an international economy.