At the weekend Sebastian was still jailed, but Gustavo was released. He is among the few dissidents who have not been jailed. Recently the government charged leaders of the tiny social-democratic Harmony Movement with attempting to recruit within the Army and Interior Ministry. True or not, the charge itself, coupled with the threadbare attempt" to equate the Arcoses with Miami insurrectionists, was revealing. So was the Jan. 3 defection of 34 Cubans to the United States in a hijacked government helicopter, which could never have gone undetected if Castro’s internal-security network were functioning with its usual brutal efficiency. By cracking down so openly on dissidents-and equating opposition with treason-Fidel tacitly conceded the gravity of his own political and economic quandary.