Cuban Missile Crisis forces. Kennedy met with members of EXCOMM and other top advisers throughout October 21, considering two remaining options: an air strike primarily against the Cuban missile bases or a naval blockade of Cuba. A full-scale invasion was not the administration's first option. McNamara supported the naval blockade as a strong but limited military action that left the US in control. The term "blockade" was problematic. According to international law, a blockade is an act of war, but the Kennedy administration did not think that the Soviets would be provoked to attack by a mere blockade. Additionally, legal experts at the
Cuban Missile Crisis island. US officials attempted to use a Corona photoreconnaissance satellite to obtain coverage over reported Soviet military deployments, but imagery acquired over western Cuba by a Corona KH-4 mission on October 1 was heavily covered by clouds and haze and failed to provide any usable intelligence. At the end of September, Navy reconnaissance aircraft photographed the Soviet ship "Kasimov", with large crates on its deck the size and shape of Il-28 jet bomber fuselages. In September 1962, analysts from the Defense Intelligence Agency (DIA) noticed that Cuban surface-to-air missile sites were arranged in a pattern similar to those used by