Dunne was promoted in the IBEW to vice president in charge of organizing for the Pacific District, which included Washington, Oregon, Idaho, and British Columbia. He served on a committee to draft British Columbia's first Workers' compensation law. When World War I broke out in Europe, Dunne saw it as an imperialist conspiracy to take over the world's economy. He vocally opposed Canadian involvement in the war. He also joined the left-wing McNamara-Mooney Defense Committee as its northwestern representative. These activities led to his expulsion from Canada as an undesirable alien in 1916.