His dissertation, "Labor and Empire: A Study of the Reaction of British Labor, Mainly as Represented in Parliament, to British Imperialism Since 1880," led him into issues in the relation of foreign relations and domestic politics, which would structure his scholarship after he returned to China.
His dissertation, "Labor and Empire: A Study of the Reaction of British Labor, Mainly as Represented in Parliament, to British Imperialism Since 1880," explored the relationship between foreign relations and domestic politics, a theme that would become central to his academic work after he returned to China.