Final answer:
The United States' prohibition of Cuban cigars and other products is known as an 'embargo'. This policy was enacted during Eisenhower's presidency in response to nationalization of American businesses in Cuba.
Step-by-step explanation:
The action the United States has taken to ban Cuban cigars and other Cuban products from entering the United States due to political difficulties is called an embargo. This trade embargo was initially implemented by President Dwight D. Eisenhower in 1960 after Castro's policy of seizing and nationalizing businesses, including American-owned oil refineries. The embargo, which is a form of sanction, has been maintained and expanded over the years, restricting not only trade but also travel to Cuba. The Bay of Pigs invasion and the subsequent tensions between Cuba and the U.S. further consolidated this embargo, which has had significant effects on the Cuban economy and U.S.-Cuba relations.