Jack's research focuses on the international relations and security of East Asia and the Western Pacific. Jack's expertise incorporates international relations, foreign policy analysis, and area studies in an attempt to explain the region's unique patterns and practice of international relations and security. His research interests include strategic partnerships, alliances, minilaterals and multilateral institutions in East Asia, Global IR, the foreign policies of China, North and South Korea, Japan, Taiwan, and Vietnam, the cultural Sinosphere and the historical international relations of East Asia, Korean reunification, Australia's foreign policy towards East Asia and teaching English for Academic Purposes (EAP). 

Jack's doctoral thesis, Pactomania 2.0: Analysing the rise of strategic partnerships in East Asia in the post-Cold War era 2006-2023, examined how a complex interplay between power, interests, and norms influenced the emergence and functions of strategic partnerships as a new regional security practice through five case studies of the US, China, ASEAN, Japan and Australia. Adopting an eclectic approach that sought to bridge theory and policy practice, Jack found that the reasons for the proliferation and functions of strategic partnerships in East Asia stemmed from an aim by states and multilateral actors to flexibly and ambigiously navigate and manage worsening competition and deepening interdependence through cooperation and common norm-building.