Watch Bombuj. This feature documentary provides a gripping retrospective of United States-Canada relationships through a study of successive presidents and prime ministers. Using archival film footage, it demonstrates that Canadian prime ministers, from John A. Macdonald down, all began their tenures by making overtures to their American counterparts. Attitudes and outcomes have varied widely. The almost comic antipathy between Kennedy and Diefenbaker, for instance, is as palpable here as is the folksy camaraderie of Reagan and Mulroney.