Italian politics, like most of Europe's hundreds of years ago, was a big mess. There was not yet unification and it was a very chaotic time in history. It was probably true, then, that the time and place required a man such as Machiavelli to take a harsh stand and get what he wanted politically.
I personally think that Machiavelli's actions was justified but was kind of because of the prince. I personaly think that Machiavelli's actions should have been based off of himself instead of someone else or what others thought about him. I personally think that Machiavelli should have only took the blame for his own actions instead of someone else's blame.