"This is from M. Corleone."

After watching Godfather II last night my husband and I started to wonder why when Pentagelli was being garroted was he told by Roth's men that it came from Michael. I understand that he then believed that Michael set him up, leading to his display at the trial, but what was the point of them trying to get Pentagelli to believe it was from Michael when they are going to kill him anyway? It's not like he would have been around to go after Michael.

Krela
Your question has been discussed on this board many times & is often the subject of much debate. It all boils down to treachery and deception. The entire Roth-Michael storyline deals with double-crossing and trying to outmaneuver one another. While Michael & Roth give the impression to one another that they want to work together, both are constantly trying to eliminate the other. For example, Roth tries to get the $2 million from Michael, with the intention of killing Michael afterward. Michael wants control of the Tropicalla hotel and Roth's Cuban operations, but plans to kill Roth afterward. Roth tried to kill Michael at Lake Tahoe in response to Michael trying to take over Roth's casino.

Whether it was intentional or not, or whether Roth ordered it or not, the buttonman who tried to kill Pentangelli was carrying out one last bit of deception - thus hedging all bets. You're correct, Krela, that it wouldn't have mattered had Pentangelli actually died. But either way, whether Pentangelli lived or died, he was under the assumption that Michael had betrayed him. And so Pentangelli was lucky the cop came into the bar and saved his life. But by surviving, Pentangelli believed that Michael tried to have him killed, which again turned out in Roth's favor. Under this belief, Michael was brought before the Senate Committee. Had Michael gone to jail, Roth still would have won by effectively eliminating Michael, albeit temporarily.

There has been lots of debate as mentioned. The line was apparently improved and kept in by FFC because it fit the plot. Here's what we know:

1) Michael didn't order the hit.
2) Roth organized the hit, and admitted to it in a roundabout way in the rant about Moe Green.
3)The more you think about this point, the more irrelevent it becomes to the plot. This is not really of much matter since if it weas a legit hit that was botched, Roth totally made up for it admirably. If it was a set up, it worked out wonderfully. I would like to venture that it was a straight hit because Roth had already arranged a hit on Mike in Cuba, so he would most likely want to take out Pentangeli to consolidate more power for the Rosattos. It has been suggested if it was indeed a straight hit on Pentangeli that Rosatto said "MC sends his regards" or whatever he says to shake him up before he dies; that would be a pretty harsh thing to say before you were capped.

I always thought that Roth told th Rosato Brothers it was from Micheal.
You see, the Rosatos and Pentangali pretty much hated each other. Pentangali could not kill them because it would boch up Micheal's business plans with Roth and the Rosatos could not kill Pentangali because then they would have the whole Corleone family coming after them.
But if Roth told thhe brothers that Micheal wanted Pentangali dead, then they semi-stupid Rosatos would go ahead with the hit.
At least thats how I see it.

Danny Aiello, who played Carmine Rosato, admits he ad-libbed the famous line. But it’s also possible that Coppola, the most careful of directors, allowed it to remain because it fit the plot, even though Carmine intended to kill Frankie all along. “Michael Corleone says hello” was intended not for Frankie-—but for Richie, the bartender, whose ginmill was being used to set up Frankie.
It’s obvious that Richie is a “civilian,” not a Made Man, and he’s nervous as hell about his bar being used for a murder (“Carmine, NO, not HERE!” he screams after the cop enters and Rosato draws his gun). Carmine knows that Richie might be squeezed by the cops investigating Frankie’s murder. Richie would be too fearful of Carmine to identify him as the killer. Still, as a civilian, Richie is not bound by the code of omerta. So Carmine hands Richie something he can give the cops so that Richie can get off the hook: “The murderers said, ‘Michael Corleone says hello.’ ” That line would set the police after Michael, and would be picked up by the press-- another nail into the coffin of Michael Corleone’s “legitimacy.” Clever Roth!