Welcome Primo.

I have long thought that Michael should have allowed Fredo to believe he was more important to the family than he really was just to keep him satisfied enough not to betray him. When Sonny dispatched him to Vegas, Fredo was proud that he was going to "learn the casino business." Michael was so self centered, he had no empathy for those around him, and since he never needed Fredo for anything he never took into account how Fredo might be feeling.