I bribed aska to declare war on pacotello to get him bussy so pacotello my neighbour won't dow me .
The AI can do that too...
I've played quite a few games with Venice with Pocatello nearby or not far enough.
He's not too much the type to DoW you normally, but against a player who goes for a peaceful, Wonder spamming Venice it's almost a certainty Pocatello won't remain a friend forever.
Every time I've had him in my Venice games and he was too close, he proved to be a duplicitous and hypocrite backstabber (he's no Hiawatha you can manage to keep friendly and happy from the first meeting to the end of the game at times...). He turns against you if you're too far ahead of him, and he turns against you if he becomes a runaway. He's one of the AI who like to hide their true feelings from you. He usually just Denounce you, though (but I suspect he was the one bribing Monty to DoW me repeatedly in a game. Poor Monty DoWed me from a continent away and never sent units and never offered peace before 10 turns, so I'm pretty sure he was bribed). When Pocatello DoW you it's generally a one-time attempt when you've let him become too strong without reacting by a build up too. If you bloody him, he generally won't return for more later as the aggressive AI do.
In time he reveals his true feelings, and you suddenly see he's very covetous of your lands and very pissed off about Wonders. He also gets easily angry about competition over CS... but most often he hides all three modifiers from you. He's also easily sour if you have different Ideologies. If he picks Autocracy, he gets fairly aggressive (I've got a few games with Pocatello ranking first in military power)
When he's on a different continent than you, he's not problematic and a better friend.
The game's hardly "broken" because the AI make some efforts not to let you play a purely builder game in a sandbox.