Did Michael regret killing Fredo?

Could you elaborate on the motivations and emotions behind Michael's actions in the context of the paragraph "Did Michael regret killing Fredo?" Were there any moments of hesitation or conflict within him before he made the decision? Was there a sense of remorse or justification in his mind afterward? Furthermore, did the consequences of his actions weigh heavily on him, or did he view them as necessary for the greater good? Ultimately, what do you think drove his decision, and did he truly regret taking Fredo's life?