Mon étude s’est concentrée sur la prise en compte d’intérêts commerciaux dans la politique énergétique publique des années 2000, la Turquie agissant comme un acteur privé, privilégiant les profits à court terme sur d’autres bénéfices plus indirects. Cette découverte a soulevé une nouvelle question sociologique, celle de savoir quel environnement politique a pu faire émerger cette orientation mercantile, et comment. J’ai identifié comme différents facteurs l’accès à l’économie de marché, l’orientation économique accrue des politiques, l’accès de nouveau acteurs à la politique, et les changements institutionnels qui ont permis la mise en œuvre du changement, notamment la réforme administrative en profondeur qui a eu lieu depuis les années 1990. C’est ainsi que j’ai choisi, pour évaluer le poids des réformes institutionnelles sur la politique, d’examiner ici le cas de la Turquie pendant les négociations du Projet de Corridor Sud (-Southern Energy Corridor Project- ou SECP) sous l’angle des conséquences directes ou indirectes qui apparaissent lorsque l’administration étatique évolue. / This thesis explores the question of what changes when state bureaucracy changes, via an analysis of the Turkish government’s policy making during the negotiations for the Southern Energy Corridor Project (SECP). A technical analysis of the SECP in the international energy diplomacy context is first presented and – along with a historical contextualization of oil and gas transit projects in Turkey – provides inputs into a sociological analysis of how decisions were taken by the Turkish government. In the light of these analyses, I explored what the SECP process says about Turkish politics and what Turkey’s experience shows in relation to sociology literature. As I initially observed there was market-driven policy-making during the SECP process (which was new compared to antecedent technically-comparable-project decision-making process), I hypothesized a change had been realized in Turkish bureaucracy, causing a shift in dominant values and interest. Referring to literature on how bureaucracy’s dominant power over society limits liberalism, I claimed this process could replace a strong state with a modest state, and a weak society with a stronger one where the market economy and its values became dominant and more liberal and democratic politics could interact. However, I concluded this was not so: the market driven policy making observed during the SECP was an exception in this specific case and institutional changes surrounding the energy policy-making arena remained limited to the replacement of old actors and institutions with new ones. This created new forms of power motivated by short-term commercial benefits, instead of creating the conditions necessary for more liberal politics to interact.