Brian Leiter would do well to consider and live by the following prudential analog of Ockham's Razor:
Do not multiply enemies beyond necessity.
Why not? Well, it is just foolish, especially for a vain and status-obsessed careerist who craves name and fame, to attack people who, it can be expected, will expose his petty and absurd behavior.
One of the puzzles of the Leiterian psychology is that he does things that are quite plainly not in his self-interest. When he attacks those who are above him on what he perceives to be the Great Ladder of Success, he reveals his envy. When he attacks those he perceives to be below him, he reveals his pusillanimity.
In Aristotelian terms, what Leiter lacks is magnanimity (megalopsychia, great-souledness). The sphere of magnanimity is the sphere of honor and dishonor. Magnanimity is the mean between the extremes of vanity and pusillanimity. The magnanimous person knows himself and is capable of honest self-evaluation. This self-knowledge keeps him from both vanity and pusillanimity.
The vain man pegs himself too high: lacking self-knowledge he fancies that he deserves honors and emoluments, perquisites and privileges far above what he actually deserves. So we could say that vanity involves an excess of self-love together with a lack of self-knowledge. Leiter is clearly vain in this Aristotelian sense. His vanity is at the root of his envy of those who are his betters, such as Thomas Nagel whose superiority is evident and unsurpassable by the likes of Leiter no matter how hard he climbs.
The pusillanimous person pegs himself too low: lacking self-knowledge, he fails to aim at goods he is worthy of. He occupies himself with matters that ought to be beneath him such as slandering and defaming opponents.
So it appears that Leiter, lacking self-knowledge and with it magnanimity, oscillates between vanity and pusillanimity. When his vanity is in the ascendancy, he attacks those above him on the Ladder. When his pusillanimity reigns over his psyche, he attacks those below him. This is yet another proof of the appositeness of the 'Ladder Man' label. It is not just that he obsessively likes to rank things. He himself is obsessed with his rank, and thus obsessed by those above him and below him in the Rangordnung. He cannot accept with gratitude the rung upon which he is perched, however precariously. He burns for more in the way of name and fame while denigrating those he considers unsuccessful.
Leiter is a fascinating study, not qua token, but qua type. The Ladder Man type is what elicits scientific interest. There is no science of the particular qua particular, said Aristotle. Individuum ineffabile est.
For Aristotle on magnanimity and pusillanimity, see Aristotle, Nicomachean Ethics, Book IV.