Yeah, Giuliani was one of those ambitious NY DA's. Rudy got a "plea bargain" with Michael Milken only after he threatened to ruin Milken's brother, as he really didn't have a viable case against the "man" himself.
But at least Rudy did have some real accomplishments and did heavy damage to the Mafia, cleaned up some union influence and government corruption in NY. Others just went after "big pockets" using "legal" intimidation and financial blackmail - really just an extortion tactics, not much different from Mafia's - and got fat settlements that never compensated the victims, if there were any.
Spitzer was a "good" understudy, it would seem.
As to Rudy, the innocent people ruined could be viewed as collateral damage.
Financial blackmail, you mean like Jesse Jackson too !