Trapped on Earth

Source: XKCD

Sometimes I wonder if in a few million years some advanced alien race will show up at Earth. They had long ago filtered out all of the radio noise in the galaxy, narrowed down the planets likely to hold life, and finally set out to explore the galaxy.
As they neared our star system they would do some scans and find that the third planet from the sun had a good atmosphere, a warm climate that could support liquid water, and even - to their joy - it was surrounded by thousands of tiny bits of metal; manmade satellites.

They would try to hail us, but would receive no reply. They would come closer to our planet and notice a few man-made objects on Mars. Their stomachs [or whatever they have] would twist with excitement at their realization that we too had the power to leave our planet and travel in space.

They would reach earth and scan it. They would only find primitive cities, barbaric savages, and derelict automated machines trying desperately to fulfill their futile mission. These humanoid barbaric savages couldn't be the ones who built the satellites and the man-made objects on mars could they? Something must have happened to them. Who was that once proud race that once beamed messages into space and sent robots all throughout their star system?

I wonder if the human race will really amount to anything other than a fascinating line of rubble in the fossil record. We refuse to seek out alternative sources of energy, we are so territorial that we kill our own species, and people are even suggesting we should abandon sending people into space altogether.

We are overcrowding this planet, we're killing much of the life on it, and no one seems to be getting it through their thick skull that this is the only planet that we have. That's it. We fuck it up and we're dead. There is no escape hatch, no reset switch, no backup planet we can jump to.

We have to work hard to leave this planet and colonize other worlds. We should be treating other planets the way we treat other continents: take it over and breed like mad.