 In sympathy with his efforts to promote the CCP to the outside world, Zhou arranged for a Canadian medical team, headed by Norman Bethune, to travel to Yan'an, and assisted the Dutch film director Joris Ivens in producing a documentary, "400 Million People".Zhou was unsuccessful in averting the public defection of Zhang Guotao, one of the founders of the CCP, to the KMT.Zhang was prepared to defect due to a disagreement with Mao Zedong over the implementation of the united front policy, and because he resented Mao's authoritarian leadership style.