^ Right, but the Federation is the only one with the prime directive. The Romulans, Klingons, Ferengi, Cardassians, and how many others may choose to give or sell technology to a species at any time. So there's got to be alot of races running around out there with warp technology that they did not invent on their own.
Anyway, my point was that I don't understand why achieving faster than light space travel is somehow a measure of a culture's development. Sure, that happened to be a driving force in Earth's transformation into a peaceful world, but only because it happened to be noticed by the Vulcans who then made first contact. It's not like the technology itself is somehow a magical device that will make everyone on a planet forget their grievances with one another.
Frankly, I think simply saying "we contact those who are warp capable and leave alone those who aren't" is way oversimplifying matters and leaves alot out of the equation. There's alot more to how developed a society is than whether or not they've figured out how to make a warp engine. The TNG interpretation of the prime directive seems to say that interaction with a pre-warp culture will contaminate their natural development, but contacting a culture with warp will not, which I just don't get. There are great differences in warp cultures. Look at the Enterprise era vs. the TOS era vs. the TNG era. Totally different worlds. Imagine how a replicator or a photon torpedo could affect a culture that had achieved warp but not those other things.