Zasa came to Michael’s party to get his permission to whack Vincent, whom he described as “a stone in my shoe,” wants to know if “he is your problem or my problem.” Michael replies that “your business is your business… I’m out.” Vincent is ushered in, insults Zasa, says he’ll kill Zasa. Michael’s response is to chide Vincent, in front of Zasa: “Mr. Joe Zasa now owns what used to be the Corleone family business. Out of the kindness of his heart he gave you a job in his family. Contrary to my advice, you took the job. I’d offered you something, better, in the legitimate world. You turned me down…” He orders Vincent to “Make your peace with Mr. Joe Zasa. C’mon…” Had Vincent meekly submitted and made up with Zasa, or simply stormed out of Michael’s office, he’d have been dead before dark. Instead he bites Zasa’s ear—the ultimate Sicilian challenge. Michael relents: “Maybe you should come with me for a few weeks. See what happens.”

All of this is a device by FFC to introduce us to Vincent and put him at Michael’s side. But, I’m wondering: Was Michael testing Vincent? If Vincent had submitted to Zasa, would Michael have let Zasa get away with whacking him, as he appeared to be prepared to do? Or, was Michael testing Vincent to see if he’d put his life on the line for his uncle?

Your thoughts?

Since no one has shared their thoughts, I'll give mine:

I think Michael would have let Zasa kill Vincent. Let's face it: A guy who had his own brother killed wouldn't have many warm-fuzzies for an illegitimate nephew who he didn't even invite to his party, whom he offered a good job with him in the legitimate world and who turned him down to take a job with Zasa, and who foolishly provoked and took on a much more powereful man. More important: Michael had only hours before been "blessed by the Pope," and had just forked over $100M to Archbishop Gilday for charity. Why would he let Vincent drag him back into the gangster world? As he said to Vincent, "So kill him--what does that have to do with me?" Same would have applied to Zasa: As long as Zasa didn't explicitly say he was going to kill Vincent, it'd be a case of "don't ask/don't tell." If Zasa had killed Vincent, and made his body disappear so as to avoid embarrassing Michael, I think Michael would have let the whole matter pass.

But, Vincent biting Zasa's ear was a step too far in that scenario--Vincent forced the issue. I also think Michael, ever the manipulator and user of other people, did have it in his mind to test Vincent. And Vincent showed that he'd put his life in jeopardy for his uncle. There was a guy Michael could use, especially since Neri looked like he was ready for assisted living.

There is something of a thread through the movies where Puzo and Coppola are baiting the audience - surely Michael's changed enough that the brutality is beyond him now? Then he goes ahead and does it.

I don’t think so. Like FFC said on the commentary Mike doesn’t care about the in and outs of outsmarting mob figures like he did in the previous films. I think he wanted to help save Vincent’s soul and didn’t want him to go down the same path he did