Does it really make sense that Hagen has a mistress?
In the book we find the following passage:

This implies that something like having extra-marital affairs can be dangerous. If that's true, why should Tom, the most rational person, take such a risk?
My guess: FFC invented this phrase for the sake of the scene, to make the humiliation stronger: If Tom has a mistress, Michael would be probably one of the few people to know.

As you may know, Danito. In the original GF II script, Tom's mistress was Sandra, Sonny's widow. That's the main reason Michael disapproved.

Michael is the son that is most like his father, right? And Vito was straitlaced and devoted to his wife. Vito didn't cheat. He understood it in others but he considered it a weakness, a mild one as things go, but still a failing. Michael likely would have felt the same way.

I think Hagen's concern over Sonny's affair was exactly what their father said later about Sonny's brain going soft from all the comedy he was playing.

Yeah definitely FFC wanted the Michael character to humiliate Tom in a very personal way by letting him know that Tom had no secrets from Michael.

Tom likely had a mistress for the same reason any other man would.

Wasn't there a film idea that was dropped that Tom and Sonny's widow were supposed to be (ahem) close? If that had been left in that might had further explained/justified Michael's coldness.

Yes, I mentioned that in my post, Lilo.

I think we've all pretty much agreed that Mike never forgave Tom for Sonny's death and the Corleone troubles generally. So, he used Tom's affair to twist the knife. But maybe FFC included his affair to show that Tom had fallen not only in Mike's eyes, but actually - that he just wasn't the same man anymore.

A subtheme of II is how Neri attempts to push past Tom to become Michael's #2. When Michael says, "...take your wife and your mistress," note how the camera focuses on Neri and his smirk. I took that to mean that Neri was the source of the info.

Danito's comparison with Soinny re. the dangers of having a mistress is well taken. Perhaps Tom, having been excluded from critical aspects of the family business, felt he could afford to indulge himself.

Amazing Turnbull ! just saw that !

What is evenbetter is what happens next. Tom asks Michael why does he hurt him all the time, and protests his loyalty, then in Italian Michael asks if he is staying, and Tom replies that he is.

Then immediately Tom goes into his non-wartime consigliere mode. He tells Michael he's won. That he doesn't have to kill anyone. That it would be impossible to get to Roth.
He gets flushed and asks "Do you have to rub everyone out?" And Michael says "Only my enemies." This is really for the benefit of Rocco and Neri, not Tom.
And Michael lets him have it again. He says "You surprise me Tom." Says history proves you can kill anyone." Then he turns to Rocco who immediately contradicts Tom on Roth saying the hit is "difficult, not impossible."

Tom then is further humiliated not only by Michael but also by Rocco and Neri (who were both in the room with Michael before Tom came in.)

Inexcusable.
The "benefit" for Rocco and Neri was that, by humiliating Tom publicly, he made it impossible for either of them to disagree with whacking Roth. So, when he turned and said, "Rocco?" poor Rocco had no choice but to say, "Difficult, not impossible" if he didn't want to be put in the same sh*t-can that Michael had just put Tom. It was Michael at his most ruthlessly manipulative.

Exactly, and he was also playing Rocco so he would think that if he volunteered to go on the Roth suicide mission and somehow survive, he would become Neri's equal.

Great points. I never read the original GF2 scriptdoes anyone know where I can see it?

I was looking into the issue of Tom's mistress and found this thread. Is it considered canon that Sandra was Tom's mistress, or is that just insider stuff that (some of) us inquisitive types have managed to dig up but was not intended to be known? I am fascinated by the possibility.

TIA.

I don't think there's a consensus about it. Yes, I think that among the plethora of sources that Board members cite there is language about Tom's mistress. Of course, GFII makes specific reference to it. Some speculate that, at least for a time, it was Sonny's wife (or widow).

One of those things that I may have hallucinated after being through the discussion through the years: wasn't some footage shot of Tom with Sandra, that has never been included in any cut of the film?

As I've mentioned on here before, I think Michael's abuse of Tom in this scene is intended to get a "blank check" from Tom ("You gonna come along with me in these things I have to do -- or what.") that includes Tom's pre-approval of the murder of Fredo.

Here's a link to the GF II alternate script. This is the source of Tom's affair with Sandra Corleone.

That script was the final one before shooting started 6 days later. However, parts of it were either left out of the final cut or changed during production. Some of the film material had been restored in the Saga, but there is still a lot of footage gaining dust in some archive.

The novel makes no mention of a mistress, and the only reference to a mistress, in GFII, doesn't identify her. But, Sandra wins by default: I can't imagine Tom spending enough time away from the compound to even meet another woman, much less woo her.

At one time I was going to start a thread: "Did Tom have a life?" I didn't, because he didn't. Can you imagine Tom telling Michael, "Hey Mikie, I'm taking Teresa and the kids to Disneyland. See you in two weeks."

Good appraisal TB. Tom didn't have much of a life because he was so dedicated to Vito and then to Vito's memory. However, I would be disappointed to find out that Tom did have an affair; he and mam were the only ones with virtue (?).

Catholic doctrine considers the "brother's widow" relations as incest. (It's what got Henry VIII in trouble.)

That theme comes back in GF-III with the first cousins. Quite naturally, Michael would be sensitized to this.