I had a pretty surreal experience playing a game as Korea recently. I had civilized, gotten secondary status, and had made protectorates out of Atjeh, Brunei, Dai Nam, Cambodia, and Nejd. I noticed the Russians had declared on Mecca (forget the country's name), and to beat them to the punch, I declared on them too and annexed it also. I wanted these territories because they had wool which was always popping up short on the global market, despite my 4th place prestige.
Anyhow I knew going in that I was going to be going over 25 badboy, but I thought it would be fun to try, I hit around 27 after that declare. What happened next is this. Japan declares on me for containment, and seeing that their armies were the same size as mine, I figure why not just sue for peace and give them containment, building back up in 5 years. I needed more modern units anyway.
Next Netherlands declares on me dragging in the UK and Ottomans, also requiring containment. I can see that I'm at a loss but I'll take 5 years of truce with the UK in this spot, so I take the peace offer. I'm triple contained now, I have 7 brigades left and no navy, and probably worst of all am down 75 prestige (but still in 4th/5th).
Five years later I'm rebuilding my armies. I'm trying to make guards but can't get the resources I need so I'm left with unstarted production and am not really fixing it quick enough. Ottomans take their chances and declare, demanding Nejd. I'm completely beat, and I'm forced to retreat off the Arabian peninsula while I lick my wounds, but I'm determined not to give up territory.
What happens next makes me laugh, but I'm sure there's a logic to it. USA is the #3 power and the Ottomans are #8. I have been sending them diplomats, and they and are the closest to sphering me. I haven't been able to ask for an alliance. But they intervene in the war anyway, and pretty soon, without me having to engage a single unit, they've blockaded them everywhere and have taken over as war leader, winning the status quo without me having to fight a single winning battle. As a result, the Ottomans are kicked off the GP list and I cling on to second power status.
I joke about it that they sent in the marines for me. Looked like a 19th century world police action, haha. But I'm sure the AI had its logic for wanting to help me. If you can arrange the settings where the AI will want to help... not that I know how... they will.