There was no 'last chance' for Fredo either in Havana or when he returned home.

Once he confirmed with his own stupid slip in front of Michael that he was the 'traitor'...he was a dead man.

Whether it took weeks, months or years...it was only a matter of time.

Apple


A wise and frugal government, which shall leave men free to regulate their own pursuits of industry and improvement, and shall not take from the mouth of labor the bread it has earned - this is the sum of good government.

- THOMAS JEFFERSON