The ethics of the race for Mars

The most recent episode of CBC's The Nature of Things, entitled Destination: Mars, offers some food for thought.
The doc looks at why we might want to go to Mars, and why, now more than ever, the race to get there is gearing up and getting very serious. Yes, President Obama has made an American commitment to a Mars landing, and there are all sorts of preparations, models and tests already underway to that very end. But The USA is not alone in its ambitions: Europe, China, India, even the United Arab Emirates have all outlined their own plans. There are already 13 satellites from a variety of countries orbiting Mars, with several more en route or planned.
In addition, there are several private Mars projects underway, from Elon Musk's SpaceX to Bas Lansdorp's MarsOne to Jeff Bezos' Blue Origin. It seems to be the project of choice for the world's unfulfilled billionaires.
And it's here that the impetus behind some of these schemes becomes interesting ... and alarming. There is some pretty loose talk about mining, property rights, propping up a failing aerospace industry, even terraforming (some plans include deliberately-induced rampant global warming, even thermonuclear blasts). It sounds like the Wild West all over again, and you have to think that the objectives and aspirations behind some of the plans are perhaps less than honourable.
But there are also voices of reason. Some scientists argue that Mars should be maintained as a kind of national (or international, even supranational) park, and should be investigated but not developed or altered in any way. Other warn that looking on Mars as a "fall-back" option for a human race that is rapidly ruining our native planet entirely the wrong reason for  push towards Mars exploration, and can only distract us from Job One, which has to be to protect and save the Earth and all its other species from the impending environmental disaster that threatens it.
And this is not the only tricky ethical choice that Mars presents us with. The idea of countries like China and India, that can't adequately feed their own populations, ploughing billions of dollars into space exploration seems morally repugnant. And the same applies in a less obvious way to developed countries like America, Canada and the EU - if they can afford to invest billions in (admittedly scientifically interesting, but nevertheless frivolous, uncertain and potentially even disastrous) schemes like the race to Mars, then shouldn't those billions be put into climate change measures, healthcare, poverty alleviation, etc? What is the moral path here?
On the bright side, it was interesting to see how many women were involved in these heavy science and engineering projects, several in quite high positions. Interesting too that they were mainly the ones with the more responsible and less rapacious attitudes.