Where did it go wrong?

I look at the concrete jungle before me, 

A collage of every shade of grey you can dream up

I see smoke billowing up into the cloudy day

Seemingly clumping together to form a cloud of death

I think to myself, “Where did it all go wrong?”

It once was a blue, vibrant rock

With singing creatures

With nature's creations

A world in which your worries flushed away

But as we grew, our greed followed in our footsteps

And one day, 

You could hear the singing no more

The hills metamorphosed into shells of their former selves

The crystal lakes, drained of their glory

The fauna, silently suffering from our creations

And soon the land lay barren

The uniqueness of this place, the life that once thrived, all gone

And now I can see the answer

It all went wrong when we went against nature