Is the character of Leroy Jethro Gibbs, as played by Mark Harmon in the U.S. t.v. program, N.C.I.S., an accurate portrayal of an ex-United States Marine Corps senior N.C.O. ? I am not going to inquire as to the accuracy of the show in general, as I just like the thing, a helluva lot more than I used to like C.S.I. anyway.