The nationalist issue among left-wing movements was often apprehended through an analytical perspective which is rooted in political theory. On the other hand, few are the works which tried to study this relationship between left and nationalism in the literature related with party systems formation and consolidation. Faced with this under-treatment, what we suggest here is to interpret the historical-institutional conditions beyond the integration of the national question within the discourse of a left-wing party : why in a same party system two left-wing parties will opt for opposite stances about nationalism ? Why does one choose to integrate national ideals within its ideological and programmatic framework, while the other will advocates multiculturalist and/or internationalist positions ? Through a case study on the Turkish party system, we will explore the conditions under which the local left – embodied by the Republican People’s Party (Cumhuriyet Halk Partisi – CHP) and the Democratic Peoples’ Party (Halkların Demokratik Partisi – HDP) – adopt radically opposed views on nationalism. Taking inspiration from the cleavage theory (which was conceptualized by Lipset and Rokkan), we will analyze first the historical critical juncture which constituted a fertile breeding ground for the birth of a Turkish version of the cleavage opposing « center » and « periphery ». Then, we will describe (through a discourse analysis) how the CHP and the HDP respectively align themselves with the two opposite sides of this cleavage. This study will be followed by a focus on the two respective sociological bases of their two electorates, and on their respective geographical areas of strength. Lastly, we will show how the recriminalization of the Kurdish issue and the ongoing military operation in Northern Syria create a « nationalist consensus » which distinguishes even more sharply the two rival parties within the Turkish left.
