Senate Foreign Relations Committee chairman Jesse Helms (R-N.C.) was talking pretty tough today when he introduced a bill to tighten the U.S. embargo against Cuba and yank financial aid to any former Soviet country that helpsPresident Fidel Castro. Helms said he will not be satisfied until Castro is gone. "Let me be clear," the senator said, reverting to Cold War lingo. "Whether Castro leaves Cuba in a vertical or horizontal position is up to him and the Cuban people. But he must -- and will -- leave Cuba."TIME Miami bureau chief Cathy Boothreports that Helms gets many of his ideas about how to handle Cuba from Rep. Lincoln Diaz-Balart (R-Fla.), a Cuban emigre who happens to be a distant cousin, and sworn enemy, of Fidel. Castro is, of course, used to such threats from the north. In an interview withTIME Managing Editor James R. Gainesand other editors that took place before Helms made his comment, the Cuban leader noted laconically: "The Cuban people have been able to endure, and we have been able to maintain the maximum support to endure." The interview is scheduled for publication in next week's issue of TIME.