Define "leadership."
If you mean POTUS, then it's re-election regardless of the individual in office (or his party keeping the office if in 2d term). The odd national interest does come into play.
If you mean SECDEF, then it's all about budget and/or ego as far as "best interests."
If you mean SECAF and/or CSAF, see SECDEF.
If you mean MAJCOM, see CSAF.
If you mean WG/CC, it's often, but not always, about the next step up the ladder.
If you mean SQ/CC, see WG/CC.
If you mean the bro on the Air Staff and/or AFPC, he/she is simply trying to survive a very ugly assignment with long hours filled with pain and doing whatever he/she can to make the bad man go away until he can get back out to the field where usually, not always, the tempo to SQ/CC is picked up.
Save yourself some time and heartburn; get cynical now.