The one breakthrough we need to go even further than that, in my opinion, is effectively using hydrogen+hydrogen nuclear fusion as a fuel source. Then we could just establish our main base around Jupiter and stick a hose into the planet and voila, free fuel for everyone.
As cool as that sounds, if we start colonizing the solar system, chances are people are going to branch out if it's possible. People are going to find ways to live on as many planets as possible. I know that the technological barriers are much greater than that of, say, the Oregon trail, but presumably by the time we have colonized an environment as hostile as the moon or mars, we will be at least a little more nonchalant about space travel at the least. People will expand to the area available to them. People with differing viewpoints and conflicting aspirations will push for colonies elsewhere. Then they will all multiply. By the time we fill up the livable parts of the solar system, I fear we would have enough people using enough energy to have some level of impact on Jupiter. I don't know what exactly, but we should bear that in mind before we go raping planets for their energy. After all, we've seen how well it worked out for Earth.
Don't be silly. Mars is no place to raise a kid, and there's no one there to raise 'em if you did...
Now that you mention it, I've heard that it's cold as hell.
So what you did to that puppy when you were 7, yeah, we'll always know about it.
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Seven puppies were harmed during the making of this post.
I take it you're speaking from personal experience?
Living on Earth may be expensive, but it includes an annual free trip around the Sun.