In the aftermath of the terrorist attacks of 11 September 2001 (9/11) in the United States (U.S.) the U.S. and Canada both restructured the institutions responsible for the management of the U.S.-Canada border. The United States created Customs and Border Protection (U.S. CBP) under the Department of Homeland Security in 2002 and Canada established the Canada Border Services Agency (CBSA) under the Ministry of Public Safety in 2003. Prior to these reforms, in both the U.S. and Canada, the border was under the jurisdiction of multiple government agencies and departments, including those associated with immigration, customs and policing. This thesis utilizes the concept of path dependency and the organizational behavior model to examine the post-9/11 institutional changes and the extent to which they impacted the management of the U.S.-Canada border after 9/11.

Since the 2019 territorial defeat of the Islamic State (IS) in northeastern Syria, thousands of foreign nationals affiliated with the Islamic militant group have been detained in refugee camps and prisons in the region - the humanitarian conditions of which have come under increased scrutiny. As a result, the repatriation of these individuals has become a contentious migration-related policy issue and has led to diverse state responses. In the North American context, there is a striking contrast between Canada’s ‘passive’ approach and the United States’ ‘active’ role in these repatriation efforts. Through a comparative critical discourse analysis (CDA) using Fairclough’s methodological three-step framework and Balzacq’s sociological securitization theory, the public rationale of Canadian-American policy diversion is explored. As a result, this study contributes new knowledge to the field, providing unique insights on how and why two closely-allied countries justify their engagement with IS- affiliated citizens in fundamentally different ways.