I. Report From Havana.

On the eve of the eighth anniversary of the 26 July Movement, in 1952, on which Cuban revolutionary leader Fidel Castro attacked Batista's Moncado, Barracks, the heroic struggle of the Cuban people for independence has reached its worst crisis. Oil and sugar are the gremlins in a revolution that otherwise has operated with surprising smoothness. Oil, Cuba's only fuel, sugar, its major crop and major foreign-exchange earner. Through these two products, the U.S. is delivering its greatest blows so far in the diplomatic, economic and propaganda offensive which it launched against the Castro regime soon after Batista fell.