1) Plenty of people had forsight before the ISS project was launched and knew it was ill conceived, poorly budgeted, and sold with a lot of false information

2) The point is that instead of spending the billions to tinker in space, we could've developed the other technologies with those billions. We still need those other (robotic) technologies before we can do anything really effectively in space, so why not do that first since it would be way more cost effective.

3) Since we already know how we can avoid issues with weightlessness (by creating artificial gravities with centrifugal forces), wouldn't it be more expedient to lower cost of materials to space and build bigger and better space stations and ships that have artificial gravity? Do that rather than worry about the effects of weightlessness.

4) Before we can do anythinig reasonable and sustained on mars, we need to develop robust robotic technology well beyond where we are currently. One of the most effective uses of that technology would be to run it with a station based on phobos to teleoperate mars robots.

5) you question what space robotic technology do we have at this point. Well, that is my point. We just now spent a few million to explore robotic servicing of hubble. It has taken all these years to even approach the issue, because we would rather budget billions to put a few astronauts on ISS and to continue to run the space shuttle white elephant. We had a choice on many paths to take in priority order of developing technologies to support sustained use of space. Instead of developing a robotic infrastructure which should have been a prelude to human visitation, we have done it backwards. We have used backward technology to attempt to sustain humans in space at huge costs and little return.

6) It is still not too late to properly prioritize and utilize space budgets, but inertia and bureacracy rule NASA so I have little hope of making the most of these budgets. Frankly if I was in charge of NASA I would probably write off ISS as a wrong headed project that needs to end and put all the money budgeted for its continuation into next generation lift vehicles that would improve cost and safety by at least an order of magnitude over the shuttle. (That probably means completely different vehicles for cargo and human beings).