Research on the transnationalization of social movements has been slow to emerge, given the rootedness of contentious politics at a local and a national level. Indeed, the political process approach to social movement studies had repeatedly demonstrated the relevance of domestic political opportunities—including institutional points of access and inclusive versus exclusive political cultures—in affecting the mobilization potential, forms of action and chances of success of social movements; something that is as true of ‘new’ social movements as it was of ‘old’ ones. To a large extent, social movements have even contributed to the creation of nation states, which emerged in parallel to the spread of capitalism, by focusing their struggles on national institutions and building national collective identities (della Porta, 2013).