In times of conflict, art can seem like a luxury. Yet it has always played a vital part in the making, and the attempted breaking, of nations. Drawing on art from states that formed during the same period after the first World War as our own, a new exhibition at the Irish Museum of Modern Art (Imma) is an absorbing reminder of the similarities that occupy people across the globe, even as we may battle to assert cultural difference. Initially conceived as part of the programme for the Decade of Centenaries, and with works by artists from Finland, Estonia, Poland,...