In my current game with typical large galaxy 8 player (7 random Incredible AI's) Snathi was at war with the Iridium long before the end of the first year.
I know that I play 4x space games quite differently than most and my style is to attack and conquer very early and often. I read a lot of tales of suffering here from players and while a good portion of it is a result of not getting off to a fast start, much of the rest of the suffering is due to not making military ships early enough!
If your military rating is well below a few of the other AI's you may be in for trouble especially at high difficultly levels. If your getting negative diplo modifiers due to being considered weak or worse yet, ripe for conquest, it really is time to get some warships. Ships captured from graveyards can certainly help for a while.
In time I expect the military AI to become a lot better in GC3 and then hopefully we'll see more wars and an even better game. The first step to improve the AI is for it to learn to a drive or two on its ships so they have some decent speed and can actually get to the battle fronts quickly. The next step if for the AI to research Planetary Invasion rather early if it is considering attacking. Then they can really wound or eliminate their targeted victim(s).
Many players wait until they can build nice big ships, but in reality I sometimes find it useful to build Tiny ships early on using my special resources. If the ship gets killed, no big deal as you get the resource back. I don't recall a game where I didn't make quite a few small ships as I lacked the tech to make larger ones until later.
