Turns out Clark was fired by the Pentagon, ostensibly for being hard to get along with. This is from Richard Cohen's Washington Post column, Sept. 18:

...then-Defense Secretary Bill Cohen, joined by many of Clark's colleagues, came to just plain dislike him... He won the respect, even the awe, of his colleagues, but too much of the time he did not win their friendship. The rap on Clark is that he lacks precisely those qualities that define a politician, particularly warmth and affability... even his most steadfast champion in the army, Gen. John Shalikashvili, recognized that Clark was too brash, too cocky, too driven, too self-absorbed, too hard on subordinates, too dismissive of critics and criticism - but, also, too brilliant and talented to be overlooked... the personal qualities that bothered his critics would be intolerable in a president.

FWIW...

Cheers,
Michael