Well... I didn't *like* the fact that Michael had his brother killed he's family, the thing you value most in life! BUT it was "right" for the circumstances of the story. I mean, it showed who Michael had become and if you're "into" the character, you understand why he had done so. It was a "him or me" situation.

"...Luca Brasi held a gun to his head and my father assured him that either his brains or his signature would be on the contract. That's a true story. That's my family, Kay. It's not me."
(Michael Corleone)