Yes, the problem is human nature...meaning greed...and greed is a result of fear (fear of not having "enough" of whatever it is that you think you need...and that could be land, food, water, security, love, possessions, respect, power, etc.).

Human nature has two sides: a loving side and a fearful side.

When the fearful side wins out over the loving side, that's when the trouble begins.

Love sees that there definitely is "enough" for everybody on this planet and shares it out on a pretty equal basis. Fear sees that there isn't enough for everybody and reacts by hoarding, concealing, stockpiling, denying, and NOT sharing on a pretty equal basis, but grabbing all one can get for oneself...or one's nation, group or family.

The latter tactic is leading us continually into societal decay and disaster.