Originally Posted by Turnbull
Originally Posted by Lana

Vito was expecting Barzini-Michael meeting to take place regardless of whether Vito was alive or not? Vito to Michael: Garden scene
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Now listen -- whoever comes to you with this Barzini meeting -- he's the traitor Don't forget that

Certainly Vito was expecting Barzini to move against Michael, but not him (Vito). Barzini figured Michael was weak, and would be weaker without Vito's guidance and counsel. That's why he waited until Vito died before he made his move--and why I believe Tess didn't approach Barzini right after the fishtank scene (see above).
Therein lies the issue?

Any move against Michael after their "Commission meeting and the peace agreement" is a move against Vito unless Barzini "waited until Vito died before he made his move--"

However neither Tessio nor Barzini could have 'known' when Vito will die even with "The Godfather's sick, right"?

I don't want anything to happen to him [Michael] while his father's alive!