I just don't buy that "now there's enough for everyone" as opposed to every other point in history where... contention for resources was pretty much the same. Go as far back as you want and you'll find records of war and strife, even though the planet's resources were limitless compared to the consumptive pressure they're under now.

People think that being the first soldier over the wall in a siege, veritably a death wish, was a punishment reserved for criminals or something, but actually it was a mechanism of social mobility in an ancient society. An individual who breached the enemy's defenses was honored and paid richly.

You can observe the dynamics just as readily in modern society, watching a show like Survivor which puts small-group social politics front and center. Often the players of the game wish that everyone would just go along with the plan. Sometimes it does happen, but just as often a few people see a better opportunity for themselves by breaking with the popular consensus. It doesn't even have to be the same people every time. It's just always better for some people to try going a different way: making their own alliance or their own city or country. Both the drive towards individuality and its results, strife and resilience, are necessarily eternal in the cycle of life.

If you want to be glib, there is a light and a dark side to the force.