What is Mustang's philosophy of leadership?

That leadership is not a reward for merit — it's a burden you accept to do something specific. He doesn't want the Führer's position for status or comfort. He wants it because he has a specific vision of what Amestris should become, and he calculates that the Führer's position is the best tool for implementing it.

What does Mustang teach about using power ethically?

That ethical use of power requires acknowledging what you did with power before — specifically the Ishval War. His guilt about Ishval isn't decorative. It's functional: it prevents him from becoming comfortable with the cost of the things he orders. He believes a leader who feels no guilt about harm done is dangerous. His guilt is the corrective mechanism.

What does Mustang model about accountability to subordinates?

Hawkeye is specifically there to shoot him if he loses himself. She tells him this explicitly. He agreed to this arrangement. This is the most remarkable piece of accountability in the series — a commanding officer who has designated someone to stop him from becoming the thing he's fighting against. He takes the threat seriously.

What does Mustang teach about patience in pursuit of justice?

That it's strategic, not passive. He endures Fuhrer Bradley's authority, the military hierarchy, and political obstacles — not because he accepts them as legitimate but because direct confrontation would eliminate his ability to change anything. Patience is the technique; the goal is unchanged.

What is Mustang's greatest lesson for people who want to change systems from within?

That it requires both vision and endurance, and that endurance requires understanding exactly what you're enduring for. He knows what he wants. He knows what it will cost. He proceeds. The clarity of purpose is what makes the patience survivable.