In the novel, when Tom is released by Solozzo and returns to the compound, Michael is a bit resentful when he realizes that Tom is closer to Sonny than he could hope to be. Perhaps it's a carryover of that?
Exactly. Mike never felt close to Tom. Remember the wedding reception scene after Mike introduced Tom to Kay. Mike felt it necessary to comment to Kay that Tom was not a Sicilian. Totally unnecessary.
