Egregious extraction of resources aside, we absolutely need a permanent presence on the ocean floors of the world. Just as we need a similar presence in the rest of our solar system.
For the ocean floors, however, we must begin cautiously. To the greatest extent possible, we must first understand how that ecosystem works before we place too great of a manipulative presence there. And you should understand, that is a completely different ecosystem down there, and we understand only a little of it now. One that, however different, still interacts in undoubtedly very important ways with things up here, which of course we also don't understand very well.
Interestingly enough, there is a way we could get that initial, physical presence, while still accomplishing something else very practical, in a much more direct way, outside of the oceans.
There is another public works project that I would like see our nation consider. A project that would be leveraged by the fact that the sea based, liquid hydrogen producing, Yen Tornado Turbines, project already recently described, would provide the ready made presence at sea of large scale, floating platforms. Platforms that could also support my alternative to space elevators, or rockets, as a way to move large quantities of cargo into low earth orbit. That alternative would be the world's first underwater, suspended tunnel. In this case a tunnel that would start on a deep part of the ocean floor (at the equator, naturally, and probably in the mid Pacific somewhere), and then, inclined at a somewhat shallow angle, would extend out till it exited the surface (perhaps for another 300 meters or so), down range, say, 300 miles or so. And in that tunnel would be a mass driver apparatus of best possible design.
The beauty of this, as far as the ocean is concerned, is that it provides an operations base for exploration we've never had before. A base for which the automated, and manned stuff could go out and observe, 24/7. A base of operations for exploration that would be quite separate from launch operations which would do no more than make noise, and generate heat, which, I believe could be managed adequately, and appropriately, for that environment.
This would be, you see, a chance to start the real exploration of both unknown realms at the same time, and we could do it all as a part of setting up what would be an extension (with hybrid dirigible/blimp trains) to a world public transportation system, I have also proposed.
This may seem a "dream too far" to most of you but I assure you it is not. Getting out there is fundamental to the survival of our species. That means being able to get out there in a very big way. Which then means industrial sized materials flow. And if you aren't talking something that can at least do 100 ton payloads every hour, 24/7, than you are dicking around. And precisely because this is so important, it must be made so that all people on this planet have a chance to benefit from it, and I, for one, cannot see that happening if we leave this to purely "market" forces.
Just some more stuff for you to be thinking about as you make that effort to become better informed. As well as the effort you are going to make to have something better be created with which to organize ourselves with. If not what I'm suggesting, then find a better alternative.