[Amorok]

Any alien race that came to Earth would likely observe us first before attempting contact, and the first thing that would strike them would be man's inhumanity to man. Leaving bleeding people on the street, the overwhelming violence in our media, and the history of war that goes back farther than the history of writing information down. Literally, killing each other was important to us before any method of transferring knowledge that didn't involve talking was.

This will result in one of two outcomes. Either said hypothetical extraterrestrial race will steer clear of us, probably slapping an intergalactic biohazard label on our solar system (could this be why we haven't met any aliens yet?) or the other alternative, they preemptively wipe us out utterly to protect themselves. While I think either is likely, unless you use a method of killing us that affects us and only us biologically, it would be hard to beat humanity in a conflict. The one thing we do better than anything else is kill things. The fastest developmental curve for any technology in any human culture is that of weaponry, and almost every scientific advance we've ever made has been turned into some method of killing. I don't have an opinion about it either way, but in any kind of conflict other than a brutal, effective and overwhelming surprise decimation I think humanity will eventually have an edge.