Is the Betrayer punished?

[HappyBuilder]

I had a perfectly pleasant game going yesterday - a world at peace - when one of my friends, Germany, betrayed me and denounced me. Now all of a sudden the rest of the world suspects me, because why would a friend denounce me if I hadn't done something terrible? And yet, when I look at the Global Politics screen, Germany actually reads Betrayed You (or something with the world betrayal in it).

Does the AI punish the betrayer, other than beyond the normal penalties incurred by denouncing a civ other civs were friends with? Does opinion of Germany plummet because he clearly betrayed an ally? I don't get that impression. I've never gotten a note from another civ yelling at me for failing to support a friend.

In any event, that denouncement set off a death spiral of relations and I've had 4 civs go from friendly to hostile to war almost instantly. It's an archepelago map, so I'm just destroying embarked troops en masse, but still...

HB

 

[Ellye]

The AI in Archipelago likes to band together more than usual, it seems.
Last Archiepiscopal game, I decided to join in the banding, and we had a world of global peace where literally everyone was a declared friend of everyone else until about 1700 AD, when the Ottomans decided to denounce me out of the blue.

I denounced the Ottomans back - and, to my surprise, everyone stayed on my side, and denounced them too. But no wars were fought. (and I managed to finish that game without a single war being fought except for City States).

Not sure if it was related to the Betrayal or not, though.

 

[Glassmage]

If the other civs hate you because your friend denounced you then that friend get treated worst than that. AI's hate each other equally. There is no "banding". If you refuse to participate into diplomacy because you think it's stupid and pointless then things will play out by themselves and eventually they will kill you because you have no friends.