Final answer:
The United States avoided assisting Hungarian patriots in 1849 due to its isolationist policy and the aim to prevent further conflicts with other nations, especially given the high-stakes international environment and the Suez Crisis that was occurring at the same time.
Step-by-step explanation:
The United States declined to give aid to Hungarian patriots in 1849 chiefly due to a policy of isolationism. At the core of this decision was the desire to avoid becoming entangled in foreign conflicts which could impose obligations to enter wars that did not serve American interests.
Many Hungarians were seeking assistance from the United Nations to support their precarious independence from Soviet control. President Eisenhower, observing the situation, followed the UN's cautious stance and opted not to intervene, as tensions with the Soviet Union were high, especially with the Suez Crisis occurring concurrently. This indicates the U.S. was wary of escalating hostilities during a period of delicate international relations and potential global conflict.
The aftermath of the 1956 Hungarian Revolution, where thousands of Hungarians suffered or fled after the suppression by Soviet forces, and Hungary's return to the Warsaw Pact, highlighted the dangers of seeking independence within the Soviet sphere of influence—dangers that the U.S. was not willing to confront militarily due to the potential for a larger conflict.