For the Ocean floor to be mined in this way is like dredging a river. It completely destroys the ecosystem, cutting biomass and diversity of species for years creating a watery desert, possibly decades or more.
For this sort of expensive and dangerous procedure to be on the cards, then as with mining the Alberta oil sands, the earth is starting to run out of accessible resources.
To mine the ocean floor and risk further pollutions, this will cut the amount of fish that it can sustainably produce. I am appalled and further concerned that the one Green voice in Parliament may now be replaced by another anonymous Labour backbencher.
I agree with your points here and am truly concerned... Another good reason to make this as public as possible and get public opinion before its too late.