Who is T.J. 'T-Jay' Mackey from Libra and what is their importance?

T.J. Mackey, or T-Jay, is a pseudonym for a CIA agent who was involved in multiple covert operations. T-Jay was at the Bay of Pigs, all set to go in with his men when he learned that Kennedy had refused to approve air support. This decision left T-Jay and his men hanging out to dry without anyone to rescue them. One of T-Jay's men was arrested and several others executed. T-Jay cannot remember ever being more ashamed of his beloved country.