Though both Truman and Eisenhower were ardent Cold Warriors they adopted slightly different approaches in dealing with what they regarded as the Communist menace.
With the Soviet Union in possession of the atomic bomb, Truman knew that a direct confrontation with the USSR was out of the question. So under the Marshall Plan he sought to contain the spread of Soviet influence by giving massive economic aid to those countries in Western Europe most vulnerable to Communist influence.
The thinking behind the Plan was that Communism tended to take hold in countries mired in poverty and with weak institutions of government. By helping to strengthen the economies of Western Europe—and by extension the foundations of Western democracy—the Truman Administration hoped to make it as difficult as possible for the Soviets to gain a foothold in an area of vital strategic importance to the United States.
For his part, Eisenhower was also committed to a policy of containment. Despite his persistently anti-Communist rhetoric , for example, it's notable that he made no effort to intervene after the Soviets invaded Hungary in 1956. However, Eisenhower was more aggressive than his predecessor in providing military and economic support to anti-Communist regimes and resistance movements in the developing world, especially in Latin...
Unlike the Marshall Plan, Eisenhower's policy wasn't concerned with improving shattered economies to make it more difficult for Communists to take over. On the contrary, existing economic power structures, built on glaring income inequalities between the top and the bottom, were reinforced as the Eisenhower Administration propped up the social and military elite, seeing them as a vital bulwark against the potential spread of Communism in the developing world.