The multitude of press briefings and declarations in official Washington Tuesday carried a multitude of explanations for United States intervention in Grenada. But it was increasingly apparent that underlying and overlaying all other expressed concerns, such as the safety of US citizens, was the administration's concern over the spread of Soviet and Cuban influence in the Caribbean and Central America, and more specifically its desire to stop the emergence of a ''second Cuba'' in Grenada, a development it has feared since Maurice Bishop took power in 1979.
The administration's action and the basic premise underlying it are topics of fierce debate. Much of this debate focuses on the answers to four questions:
1. How important is Grenada to the US and to regional security?
2. Was Grenada under Maurice Bishop rapidly becoming a second Cuba and a threat to the US?
3. Were the Cubans and Soviets behind last week's coup by Grenadan Deputy Prime Minister Bernard Coard?
4. Would they have taken advantage of the coup even if they were not initially behind it, turning Grenada into a Soviet satellite?
Those justifying the invasion stress, among other things, Grenada's geopolitical significance. They emphasize the island's proximity to the Panama Canal and the oil fields of Venezuela.
However, close analysis of Washington's statements indicates that the main fear for both Washington and its Caribbean partners-in-invasion was probably the domino theory. It was felt that any communist takeover of Grenada might begin to tilt the balance in the region and eventually throw the entire eastern Caribbean into Cuban arms.