Olivant and Don T, you BOTH make some very valid points. And I agree with some that BOTH of you have made here.
Olivant - I believe that in that "I'm with you know pop" hospital scene, that Michael realized that he needed to get somewhat involved in his father's business at that point. Was what he said a gesture of love on his part? Absolutely. But I also think that his saying that had somewhat of a double meaning. His finding that his father was unguarded at the hospital is what set his wheels in motion. From that point he puts his own plan into action, moving his father to another room, etc. He's keen enough to realize that they will be back to attempt to kill his father, and he uses Enzo as part of his plan. Then in the lighter scene on the steps, I believe that he took the next step towards getting involved in his father's business. That scene, in my opinion, was the defining moment for Michael. And then his getting slugged by McClusky was the decision maker, the action that made up his mind 100% for him.
It was strictly business, but it was the personal feelings that he had for McClusky that pushed him over that fine line. 2 shots for the Police Captain was NOT strictly business.
DT - The farthest thing from Santino's mind at that point was worrying about Therasa Hagen. He would leave that for his mother, his own wife, and his sister. It was not a priority at that point. I have to agree with Olivant in that under the circumstances Sonny stood pretty calm and though things out at that point. He was clever enough NOT to initially let Clemenza's people come to the compund or even let Clemenza know everything that was going on because Sonny was smart enough, in all that was taking place, to realize that it was one of Clemenza's people, if not Clemenza himself, that set up Vito.
His later asking Clemenza about Paulie, in front of the other soldiers, was not negligent or out of control at all. There really was nothing said that could tie him into the killing of Paulie. And at the same time it was, in it's own way, a pretty smart thing to let the other soldiers hear. It sent a message that if anyone was even thinking of turning on the Corleones, with Sonny as boss they would die.
As for Michael initially sensing that Sonny was not in control. I don't know about that. I think that Michael's decision to stay and protect his father, get involved somewhat, was more due to the fact that Michael was the son most like his father. A calm, cool and collective head under pressure. A trait, like Vito's, that displayed the ability NOT to act in haste, but to think things out. I really don't believe that Michael was thinking that Sonny could not lead the family or stay under control. I think that what Michael was really like deep down inside came to the surface and he automatically went into Vito Corleone like mode.
