The message is that no matter the skin color, religion, sexual preference, political leanings, species, or shape, each of us is an Earthling, our actions affecting all of us together. Wear it to recognize we are all one, or alternatively, to call attention to the fact that you're an ironic alien who doth protest too much.
Are you an ironic secret alien? Or do you simply believe that we are all one, and that we all affect each other with our actions? Whether it's humor or a statement you're after, Earthling is for you. Also available in white text on dark fabric.