Hmm I suppose that depends on just how you define violence. I think it sort of stagnates depending on the desperation of most people. It takes different forms. Sure we don't typically lynch, crucify, burn people, drill holes in their head so much anymore, but we have a more modern, "civilized" way to go about it. Technically violence can just mean unwarranted force, vehemence, etc... I think the trend of today is more to ravage peoples' minds than physical violence. There is "violence" in the acquisition of wealth, possessions, complacency... It's easy to see it in the vast apathy and deception that goes on. I think just as lies are told with words and with silence, violence is committed with swords and lies. And actually, that kind of thing has been going on for thousands of years *coughreligioncough*...just molded around what those in power can get enough people to accept.
On a primal level, I think people tend to be more violent, as well as many other tasteless characteristics, when their survival is threatened. Today, it's tough to survive in this economical debacle.
Not to be a pessimist--I think most people are good at heart, but many are ignorant as well. Take away someone's food, their shelter, their security, and people, depending on their character, will descend from the kind and caring being which is born into them. This is kind of how I define the word spirit. I'm far from religious...and I mean far from it hehe, but I like the word--which I think of as a person's character untouched--without the cynicism, bitterness, etc... which are cultivated into people from their surroundings.
So what do I make of it all, I'm not quite sure...but I think one of the major problems, with violence, deception, profit, etc...is that there are incentives for doing harmful things. A dishonest business gets more profit if it fools people, a king prevents a revolt by killing its own citizens, a president gets elected (and profits) rallying peoples' support through a terrorist ruse and religious propaganda (ahem....) You get the idea...
People can combat these things, but it is an uphill battle. I'm sure there are plenty, some even reading this answer, who would call me blasphemous, single-minded, and a dozen other things. Whether I am or I am not, it is that sort of attitude which is the problem. I think even the internet does more good than harm to the cause, because it is so vast that even governments cannot silence things. I just wish I saw more of the myth-busting on places of greater influence like Fox News.
You really do ask a loaded question, but I think the short version is that everyone is selfish to a point... I think one of the most important changes many could make is to channel that into the altruistic sense which I think we have when we're little kids (and hopefully longer). For example, I trick someone into buying something, or I help someone on the side of the road. Both things are selfish in some light. One way I get some pitiful material gain, the other, I feel good about myself. In the latter, I have satisfied some primal source of potential malice without doing harm. That is part of the potential your question is asking for, and part of the reason not to lose hope.
No one will ever meet a greater adversary than their own potential. All ya have to do is at least face it.