A constant theme in the Trilogy (and the novel) is how greed (and thirst for revenge) blind otherwise intelligent men to obvious dangers to themselves. Michael's greed for Roth's Cuban gaming empire blinded him to the obvious: Why would Roth, who lived in Miami and had business interests in Havana and Nevada, interest himself in a petty quarrel between the Rosatos and Pentangeli over three territories in the Bronx? Didn't it occur to him that Roth might be plotting to put the Rosatos in charge of the "Olive Oil Business" in NYC--Michael's muscle?.

Roth's greed for the $2 million blinded him to the obvious: Why would Michael, whose last words to Roth in Miami were, "Frank Pentangeli is a dead man," then spare Frankie and send him on a mission to "settle these problems with the Rosato Brothers"? Didn't it occur to him that Michael was signaling that he didn't blame Frankie for the Tahoe attack--and might blame Roth instead?

Michael could have had Roth squashed like a bug in Miami. Roth could have had Michael squashed like a bug the moment he stepped off the plane in Havana. Neither did. The marvel of the "This is the business we've chosen" scene in Roth's hotel suite in Havana is that, by that time, each of them probably knew what the other was up to, yet they both hung tough to the bitter end: Michael wanting to learn who was the traitor in his family, Roth for the $2 million.