The policy of containment focused on keeping communism and the Soviet Union's influence limited, rather than by trying to confront the Soviet Union directly or eliminate communism completely. It influenced US foreign policy by prompting intervention in places like Korea to stop the spread of communism.
When 90,000 North Korean troops crossed the 38th Parallel and attacked South Korea on June 25, 1950, the United Nations and the United States both went into action. An emergency session of the UN Security Council was held -- from which the Soviet Union was absent because the USSR was boycotting the UN over the exclusion of communist China from the organization. Truman announced to the American people that he was authorizing sending US troops to prevent South Korea from being overtaken by communism. The UN Security Council met again and approved a US resolution approving the use of force against North Korea. Military forces in the Pacific theater, based in Japan, were deployed in the effort. There was no formal declaration of war by the US Congress, but Congress did vote to extend the draft and also authorized the president to call up military reserve personnel for duty.
A result of the first Punic War and the Romans was the decisive naval victory against the Carthaginians at the Aegate Islands. This gave Rome full control of Sicily and Corsica. The end of the First Punic War saw the beginning of the Roman expansion beyond the Italian peninsula.
Alexander had previously prepared takeover by defeating the Persian army at Issus and captured the Mediterranean eliminating the threat of a Persian naval invasion. As well as keeping Persian land reinforcements from coming from the West, which was key in focusing on other points.
