Beijing. This resulted in the fall of Wu and the collapse of the Zhili clique in north China. Sun Yat-sen was invited to the capital to participate in discussions about China's reunification. Sun's intention was to establish a National Assembly composed of delegates from mass organizations, chambers of commerce, and armies opposed to Wu Peifu, something that the CCP had tried, to no avail, to impress on Sun in June 1923. However, the negotiations did not go well. On 24 November 1924, Duan Qirui had taken over the government replacing Cao Kun. Instead of the National Assembly, Duan favored convening a "National Rehabilitation Conference." This was opposed by Sun because it would exclude representatives from the mass organizations and would favor the militarists. On 1 February 1925, the Conference was convened and led to a break between Duan and the GMD.
Sun's trip to Beijing created divisions in the CCP. Chen Duxiu and the Party Center opposed the trip feeling that Sun should remain in Guangzhou to consolidate the achievements of the revolution. Borodin and the Guangzhou communists thought that by going to Beijing, Sun would expand the movement's influence. Borodin’s view prevailed and the CCP began publicly to support the calls for a National Assembly.
These tensions notwithstanding the tone of the Fourth Party Congress (11-22 January 1925) that convened in Shanghai was much more optimistic than that of its predecessor and delegates seemed to anticipate a rising revolutionary tide. In particular, the Congress sought to clarify the relationship of the CCP to the national revolutionary movement, to define more clearly labor and peasant policies and to adjust the party's organizational structure.
The Congress reviewed the national revolutionary movement to date and tried to outline the correct policy for the CCP with respect to the GMD. Many CCP members were finding it difficult to strike a balance between developing the GMD in the nationalist movement while not ignoring the CCP's own agenda. This tension persisted until the two parties split in 1927. The resolution reflects Chen Duxiu's caution about CCP involvement with the GMD. While "leftist" mistakes included continuing to promote the proletarian revolution and opposing entry into the GMD and the nationalist revolution for fear that the CCP would become a "yellow" party, "rightist" mistakes were defined as being more dangerous. The tendency among members to think that concentration on the nationalist movement and the GMD meant ignoring the CCP's own work was criticized as was the belief that a policy of compromise between capital and labor should be pursued.
In contrast to the CCP’s earlier May 1924 division of the GMD into a left and a right, a center was now discovered. The left comprised the workers, peasants and radical intellectuals, the right was composed of the military, bureaucrats, politicians and capitalists, and the center consisted of the revolutionary elements in the "petty bourgeois intellectual class." This center was deemed important because although numerically weak, its members occupied leading positions in the GMD. The CCP’s task was to expand the GMD-left. However, this was not to lead to the neglect of opposition to imperialism and the economic struggles of the peasantry and working-class.