The United Nations has acted already. Through the United Nations Educational, Scientific and Cultural Organization [UNESCO], the UN has been establishing above water World Heritage sites since 1972. Recently, they began declaring underwater locations as World Heritage sites. I have been fortunate to dive several of these. With the intervention of the UN and their declarations, these now protected sites are teeming with life and relatively pollution free. I'll be diving more of these sites around the world, to promote and preserve them, so they can continue to be a healthy home for all marine life.
We are all passengers on our planet, above and below ground. Let's take care of it...it's the only home we have!