Deep Sea Mining: do we really need it? 

The main thing I think about is the amount of 'dust' it kicks up. I am a resource extractor but also try to be as much of a naturalist as possible. I've been watching Nautilus and several of these underwater miners for a while now. I agree that resources on land are still technically more realistic to pursue at this time.

Just what Our oceans need!!!!

Wouldn't the first cut concerning deep sea mining be a cost analysis. Then followed by an envormental review? If the environment in that location is not studied then wouldn't the costs of studying the site drive the overall costs up? Seems to me not enough is known here to be eliminating it from evaluation?

We learn as we go forward as we have for every advancement that modernity has produced. If we apply the paralysis of analysis those benefits will take far longer. Sitting in our comfortable first world bubble we might think that's just fine, but with modern communications available to those whose desires to share in the advances of modernity they can see that it is immoral to worry about what might happen when we know their problems which could be alleviated are not because some potential problem might eventually be needed to be overcome. Cheers.

Well if climate change does collapse our societal systems and some have predicted, and food crops become scarce, then our population should drop so negating the need to use this resource for some time.

I would add also that Free Enterprise Libertarians actually use "property rights" arguments against Producers that generate pollution in that they are violating public or private property - so it's not always about Left vs Right - I'm on the political right but I agree with quite a bit on placing production constraints on companies that violate the environment as they are 'stealing' or committing theft on property they do not own - now the problem may come with degrees and reasonableness - and also falsifying data on both sides - if climate change data is not accurate that makes Producers (and workers) suspicious that other data is false - and equally if Environmentalists find out Producers are not providing accurate data on chemicals released and storage issues etc - then another trust issue - so accurate data is vital so we can get the production and also get it without living in a giant dump

What is your view on asteroid mining? That would alleviate the pressure on Earth, onshore and offshore.

I dont think so.