I'm as down on Cuba as anyone, and I recognize that Cuba's spying on the U.S. is a problem. But it's close to absurd to think that Castro would allow Cuban airliners to drop biological weapons on the U.S.
Like a missile attack, there's not enough deniability in any such plan. If Cuba is caught red-handed dropping unconventional weapons, we'd feel free to nuke Cuba, and Castro knows it.
Castro pressured Nikita Krushchev during the Missile Crisis to nuke our cities. Thanks to God, he had not access to the nuclear switch. Castro, as Bin Laden, has a pathological hatred against the U.S. and now he has the capability and the will to use biological and chemical warfare against us regardless of the consequences. Castro's possible involvement in the Anthrax attack to U.S. can not be discarded.
As an active member of the international terrorist network, Castro will not hesitate in allowing his terrorist partners to use a Cuban commercial airplane as a missile to attack the Capitol, the White House or a nuclear plant in Florida.