What will people of the future look back at and refuse to condone?
In 100 years or so, I think people will look back at how we live today and fail to comprehend, or be angered by, our seeming reluctance to do anything about world poverty, starvation and disease.
Just as we look back at slavery and refuse to condone it, future generations will be angered at our relunctance to tackle global problems. They will wonder how our minds worked, how a privileged portion of the world was able to live surrounded by riches while many millions of the earth's inhabitants had little or nothing to eat, nor medicine to treat diseases.
We rationalize away these problems and have little or no trouble accepting the current distribution of resources, but I think future generations will genuinely be stumped by our inability to help each other.