Final answer:
The Eisenhower Doctrine was enacted in response to the possibility of Soviet expansion in the Middle East, especially after the 1956 Suez Crisis. It promised military and economic support to Middle Eastern countries resisting communist influence to secure U.S. interests in the region.
Step-by-step explanation:
The Eisenhower Doctrine was a foreign policy initiative announced by President Eisenhower in 1957, aimed at expanding the scope of the Truman Doctrine to the Middle East. This policy was enacted in response to growing concerns about Soviet influence in the region, particularly after the Suez Crisis in 1956, which underscored the geopolitical significance of the Middle East and the vulnerability of its countries to external pressures. The main intent of the Eisenhower Doctrine was to provide United States military and economic assistance to Middle Eastern countries threatened by international Communism, and thereby to secure U.S. interests in the region.
In practicing the Eisenhower Doctrine, President Eisenhower sent American troops to Lebanon in 1958 to protect the government of President Camille Chamoun from internal instability exacerbated by pro-communist forces. This intervention was a signal of U.S. commitment to prevent the spread of communism in the region, as previously indicated by the assistance provided to Greece and Turkey under the Truman Doctrine.