Something more similar to what is being proposed in game is the death of a US ambassador in Libya by Islamic Extremists.
I wouldn't say so. BM characters don't die. Non-heroes, at least, and both the ambassador and hero subclasses are exclusive.
Another example, if you want, would be US ships fighting Somalian pirates. That doesn't cause a war between the US and Somalia either.
Or the US sending troops in Pakistan to take out Ossama and his men. This caused unrest, but no war.
There are many examples in which rogue/accidental/unordered attacks do not cause any escalation, as there are many examples where they do. However, they usually don't unless the side attacked was looking for war. And it usually doesn't happen when the side attacked is the weakest of the two, as it tends to be: being at the top grants you the power to whack everyone a bit, with everyone being too afraid of the risks of relation to make any kind of serious fuss about it.