Yet, anything in the water is no more than a few hours away, and any mass of equipment or supplies can be moved there in that time, anytime you like. Mars is a

Yet, anything in the water is no more than a few hours away, and any mass of equipment or supplies can be moved there in that time, anytime you like. Mars is always at best 9 months away. (Not 6 as Elon likes to lie.) Usually it would take much longer. And, how much stuff you can move at once is drastically limited. There is no need to go below just a few atmospheres worth of pressure, in any case. Little that happens at the surface penetrates very deep.