What alerted the united states that communism in cuba had become dangerous?

The event that alerted the United States that communism in Cuba had become dangerous was the Cuban Missile Crisis of 1962.

Explanation:

The Missile Crisis in Cuba is the name given to the conflict between the United States, the Soviet Union and Cuba in October 1962, generated as a result of the discovery by the United States of Soviet bases of medium-range nuclear missiles in Cuban territory.

It was one of the biggest crisis, together with the Berlin Blockade and the Able Archer 83 exercises, between both powers during the Cold War and in Cuba, where nuclear war was closest. In fact, only twice in history has a DEFCON 2 defense condition been reached in the United States.

The crisis covers the period between the discovery of the medium-range ballistic missile R-12 and R-14 of the Soviet Union (October 15, 1962) until the announcement of its dismantling and transfer back to the Soviet Union (October 28, 1962).

tenochtitlan (also spelled tenochtitlán), located on an island near the western shore of lake texcoco in central mexico, was the capital city and religious centre of the aztec civilization. the traditional founding date of the city was 1345 ce and it remained the most important aztec centre until its destruction at the hands of the conquering spanish led by hernán cortés in 1521 ce, which led to the final collapse of the aztec empire.

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