Strength of the military force and future perspective of the partisan’s movement had an important place in formulating and managing further Allied politics in Yugoslavia. The reports of the six British and Americans officers – members of the Allied military mission – have pointed out on the general conditions and straights of partisan’s movement, as well as on use value of its military power. Such a war rationale prevailed in deciding to whom to provide military and material aid until the end of the war. Also, they’ve pointed out to the perception of Tito and his place and role in the partisan movement. Western intelligence agencies were well aware that in a centralized military movement with a strong communist ideology, the role of the leader, both on the military and political level, was crucial, or rather, the most important. In this regard, the reports of John L. Maclean, an officer with the highest military rank and head of the Allied Military Mission, had the greatest practical military-political value. These reports provided deep in sights in to military-political conditions, as well as possible strategies and intentions on the ground, which were of great importance to the Western allies. MacLean’s’ reports, being the officer with the highest military rank, were crucial in providing information that contributed to understanding and decision-making regarding military and diplomatic steps during World War II. The perception of Tito as the “first” in the movement (“a head taller than all”, “a man of action rather than debate”, “not afraid to take responsibility”, “giving the impression of intelligence and determination”, “clear thinking, knowing what he wants and why, and being strong, brave, and skillful in fighting for those goals”) proved to be an accurate assessment by the Allied intelligence officers. Attempts and expectations to separate Tito from the communist ideological system were unsuccessful. During the war, Tito accepted aid and cooperation with the Western Allies, but in accordance with his own assessments, needs, and goals. This experience during the war “taught” Josip Broz Tito to accept help and cooperation with the Western Allies, who failed in their attempts to “dilute” the partisan movement and its leader’s ideological loyalty to the communist ideology and the Soviet Union. The partisan leader, at that wartime moment, knew that his rise to power in the Yugoslav capital, Belgrade, would go through Moscow. However, after the conflict with Stalin in 1948, he returned to the Western Allies who supported him in a different international context.