“A sense of humor is part of the art of leadership, of getting along with people, of getting things done”
– Dwight D. Eisenhower
In November 1945 George Marshall resigned from his position as Army Chief of Staff and President Truman appointed Eisenhower to take his place. In this role Eisenhower reported to the President, and was responsible for the all strategic and tactical operations of the Army. As he assumed his role he held three basic principles based on his experiences before and after the war.
First was he was convinced that the most effective structure to conduct military action was under the unity of command, and that the military institutions and training needed to emphasize coordination and cooperation of activities among the various services, under the direction of a single command. Second, he believed that the country needed a strong peacetime army to quickly respond to any future emergency and avoid the problems of mobilizing an army in the midst of a crisis. This required strong leadership throughout the services, with an emphasis on running an efficient organization and a unified program of military training. “Third, if such a crisis was to be avoided, there had to be cooperation among the former wartime allies. Russia and the United States were the countries whose relations would necessarily be the prime determinants of world peace.” 
However, Eisenhower soon found that he had to adjust his thinking to reflect the reality of the times. After four years of war, the country was anxious to reduce military spending and accelerate the de-mobilization process. There was constant in-fighting between the services for the allocation of scarce resources, and the relationship with Russia quickly deteriorated.
In contrast to his role as Supreme Commander where he could focus primarily on military objectives, Eisenhower now had to engage in political debates in areas he felt were important to national policies. “He confronted situations that were far more complex and far less malleable than his administrative environment had been during the war and the occupation.” 
Eisenhower dealt with the complexity and ambiguity by bringing structure and order to those things he could control, and by persistent follow up and follow through on areas beyond his control, as he tried to influence the outcomes. Shortly after assuming his new responsibilities Eisenhower held a session with his staff, to give some overall guidance and express his expectations.
He began by empathizing with the difficulty of their roles. “…no one knows better than I what tough jobs you have, how difficult your problems are to solve, and how you get irritated and resentful because of lack of progress due to circumstances over which you have no control whatsoever.” But he urged his staff not to get down.
“There is one thing in any situation that I believe is always applicable, and that is optimism and a grin. Long faces are not going to be a bit of help. Just as in war, we have to keep our heads up. Keep grinning, and keep plugging.” He expressed his desire to implement a military organization where each of the three services were equal, and under a unified command.
“We want to make certain that in establishing that kind of an organization we do not become guilty of duplications” of facilities or functions. He stressed that “we must have faith in each other. We have to depend each upon the other and believe that the other is going to perform the functions we expect of him and that each will deal with the other on a basis of fairness….So in solving problems….let us proceed on the basis that…cooperation will be as great as possible.”
Eisenhower also knew that one of the best ways to fight through complex issues was by encouraging teamwork, honesty and communication. “I could never face a body of officers without emphasizing one word – teamwork … Our attitude one toward the other has to be that of a friend expecting assistance and knowing that he will get it. If we will always remember that the other fellow is trying to fulfill our common purpose just as much as each one of us is, I think no more need be said about teamwork.”
Solving difficult problems while under extreme pressure required some finesse and “considerable tact. Above all it demands integrity and fairness. If we are honest in handling the whole problem we are certainly not going to get the War Department into a jam.” He felt that everyone needed to “act according to our own good judgment after having examined every aspect involved,” and that “tactfulness, trying to understand the other fellow’s viewpoint, and using salesmanship instead of a club, seems to me to be called for…Patience is something we can’t lose on the job. So we must be fair.”