01509nas a2200205   4500000000100000000000100001008004100002260001600043653001200059653000900071653000700080653001600087653002200103653003200125100002200157245007700179300001000256490000700266520103000273       2017                            d  cSummer 201710aBritain10aCSDP10aEU10aGame Theory10anational interest10asecurity and defense policy1 aIrina Tsertsvadze00aBritain and the Common Security and Defense Policy of the European Union  a73-860 v163 a<p>This article analyzes Britain’s position towards the Common Security and Defense Policy (CSDP) of the European Union from 1998 to 2016. It considers the reasoning for Britain’s position toward CSDP through posing the research question: Why did Britain backed the launch of the CSDP and then not consistently support all its developments? Using a case study approach, it concentrates on the main developments of the CSDP, which are: launch of the CSDP (1998–1999); development of the operational headquarters (2010–2011); role of Britain in the Libyan crisis, which is not related to the institutional developments, but still is very important as the first real chance for the CSDP to be tested after its launch.<br>Through Putnam’s Two-Level Game Theory, the article seeks to support the twin hypotheses that domestic affairs influence Britain’s decisions towards CSDP, and that developments within the European Union impact on Britain’s position towards CSDP through the interplay with domestic factors.</p>