There are many destructive forces coming from mankind itself, but they all seem to stem from a single source: greed.

Greed

The most destructive force to mankind is greed. This is the reason people exploit others. This desire to have more than one needs is never satisfied. Greed just creates more greed.

There's no excuse for some people to live in squalor while others live in excessive luxury. This is especially true when the reason those living in poverty are doing so in order for a small number of people to enjoy unlimited pleasures that only can be had at the expense of the suffering of others.

People use all sorts of ideologies, religious doctrines, moral judgments, politics, social divisions, racist theories, fear of being attacked, demonization, patriotism, ego-based sense of superiority, and all sorts of other mechanisms to rationalize the unbelievably unfair distribution of resources and the wealth they create. But in the end it's all just greed.

The manifestations of greed can be seen as early as childhood when the playground bully beats up the physically weaker children and takes their lunch money or toys. From there the child is trained to want more than others have. Being the best means defeating others. In its worst examples people will steal and even kill to satisfy their greed with no concern to how their actions affect others. And in extreme examples whole countries become complicit in killing thousands of other people in other lands to get more. Sometimes they'll even kill their own citizens if it helps to achieve their goals.

Some are so brazen in their acceptance of greed that they'll even claim it is a good thing, a necessary element to motivate productivity. In this mind-set mankind becomes deconstructed into not much more than a machine whose only purpose is to create more for the sake of having more. Taken to its logical conclusion we eventually are nothing more than gluttonous sociopaths who reject the very civility that has provided humanity with capability to cooperate so we can progress to a better life for all. Greed may produce short term gains for the few at the expense of others, but it is qualities such as cooperation, empathy, understanding, compassion, altruism, fairness, justice and freedom from exploitation that advances us to create a better world. Greed does the exact opposite.