I, of course will never break omertà! nor betray my Don!!

Sure thing “Tessio's treason” is untenable under any circumstances and there is no excuse whatsoever for what Tessio did – setting his Don up to be murdered

Vito's Rise and Rise
Originally Posted by Lana
My take, for what it is worth!
Tessio was protecting his territories rather than being "an ambitious snake"
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Barzini's people chisel my territory and we do nothing about it
Pretty soon there won't be one place in Brooklyn I can hang my hat!
Tessio should have had more faith in his Don/s and trusted their judgement

Tessio was stuck between the proverbial rock and hard place, seemingly -
  • getting no help nor support from the Corleones
  • Michael jetting off to Nevada
  • abandoning Tessio [and Clemenza] with nothing to build on

Fish tank scene
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Clemenza: Don Corleone you once said that the day would come when Tessio and me could form our own Family
Was the above Vito's empty promise carrot same as Roth's Donship to Fredo?

Don Clemenza, Don Tessio, separate and independent of each other and a la Michael / Pentangeli for monetary tribute and muscle

Besides it makes sense to me! I believe, Michael would have retained control of the "Olive Oil Business" the front to launder his nefarious stuff [if any!] which both Clemenza and Tessio need to launder their criminal proceeds It could work because they need each other