Border studies reanimated: going beyond the territorial/relational divide 'Border' has been a key category for social scientists since the 19th century when modern state-building and nation-building processes began to intensify in Europe. It is well known how Friedrich Ratzel, for example, stressed the importance of borders for 'political balance'. A lesser known pioneer in border studies is the famous sociologist Georg Simmel, for whom "the boundary is not a spatial fact with sociological consequences, but a sociological fact that forms itself spatially" (1997, page 142). He discussed the roles of borders in social life and for consciousness, and concluded: "By virtue of the fact that we have boundaries everywhere and always, so accordingly we are boundaries" (cited in Ethington, 2007, page 480). Tester (1993, page 9) condensed Simmel's ideas as follows:" The boundaries make life meaningful … but the very meaningfulness of life as something with a location and most signifi cantly a direction (i.e. life going as somewhere other than here), implies the fl ow of life over permanent boundaries." It is a sort of a paradox that the 'border' quickly became a catchword 100 years later, simultaneously when the ideas of cosmopolitanism and the postnational/denationalized world as well as the neoliberal rhetoric on a 'borderless world' appeared on the agenda. New interest was aroused after the implosion of the ideological line between the capitalist and socialist world at the turn of the 1990s, an event that gave rise to both new ethnonational borders and ethnic violence. New attention also reverberated with 'weak' and 'strong' views on globalization (Paasi, 2003). More than any other event, the 9/11 terrorist attacks in the USA and the consequent 'war on terror' generated security-related border research in which biopolitics, circulation, and technologies became key issues (Dillon and Lobo-Guerrero, 2008). Indeed, if Simmel once stated that "people are boundaries", scholars are increasingly noting how people become borders (Balibar, 1998) and how human bodies are key sites of borders in the current, biometrically managed world (Amoore, 2006). This commentary will problematize the concept of border in a situation in which the social and political meanings of borders have been rethought in academia as well as in the context of securitization of state and suprastate (like the EU) spaces, and in which bounded spaces still have a role to play in the mobilization of emotions, racism, xenophobia, and, ultimately, violence. While only two of the world's total twenty-nine major armed confl icts during 2001-10 have been interstate (SIPRI, 2011), a remarkable hardening of state borders has simultaneously occurred around the world (Rosière and Jones, 2012). I will fi rst look at how the understanding of borders has evolved and how relational thinking contests traditional border studies. Secondly, I will take some conceptual steps towards a broader understanding of state borders that highlights both their porous and not-so-open qualit...