OK, it's a little "tongue in cheek" humor, but it echoes what a lot of players feel about the diplomacy (or lack thereof) system in Civ 5. Now, I know that the AI has some grand scheme wherein it (the AI) tries to win versus Civ 4 where they merely existed alongside you.
The part of that ideology that I, and a lot of other players, take issue with is the fact that the AI will always declare war on you or each other at the drop of a hat for some convoluted reason. A few of my favorites:
1) A civ on the other side of the map / continent treks a settler over near one of your cities in order to secure a strategic or luxury resource, then a leader screen pops up saying that they don't like you snapping up every bit of land you see.
2) Again, following the same scenario as #1, the AI will become Hostile in the Diplomacy Overview because he / she doesn't like your borders touching - even though they came from across the map and settled next to you.
I'm sure we've all seen cases like that at some point or another. What bothers me about that is the fact that the AI is coded to react to close borders in a predefined way. I'm not a programmer, but if it were possible for the AI to know that you settled a city first and react less aggressively, then I wouldn't have as big of a problem with it. The same holds true for the AI considering you a warmonger even if you've never declared war, but have successfully defended yourself when the AI declares on you - it shouldn't happen like that, because by definition, you are not a warmonger.
All in all, it comes down to the point where you (the human player) knows the AI is going to declare war at some point and the only unknown parts are when and how many. It seems to me that all the victory conditions available cause the AI to go to war by the following logic:
1) Time - More cities = Higher Score = Time Victory.
2) Cultural - Puppet every city you conquer. Increased gold and science production without raising policy cost.
3) Domination - Self explanatory.
4) Science - Conquer more cities, more population for science via higher population and more trading post spam so you can take advantage of the Rationalism tree.
5) Diplomatic - Conquer more cities, more citizens working trading posts, more gold to bribe city-states with.
I could be completely wrong in my thinking, but I feel that the AI is designed to go to war regardless of the victory condition "chosen" at least 85% of the time. As a human player (yes, I realize the AI is limited in what it can do), you can decide to remain peaceful and win through 3 / 5 victory conditions without ever declaring war on the AI. However, the AI will almost always declare on someone - either you or another AI - and no matter how hard you try...you WILL end up being dragged into a war at some point.