> why would we do that at all?

This question is one of a whole genre of "why" questions that come from supposed pragmatists, but I can't help but think the existence of the question misses the entire point.

Luckily, one of the older questions of this genre was about why anyone would bother to climb Mount Everest, and ol' Mallory had such a good answer that I'll just paste the whole thing here:

> People ask me, 'What is the use of climbing Mount Everest?' and my answer must at once be, 'It is of no use.' There is not the slightest prospect of any gain whatsoever. Oh, we may learn a little about the behavior of the human body at high altitudes, and possibly medical men may turn our observation to some account for the purposes of aviation. But otherwise nothing will come of it. We shall not bring back a single bit of gold or silver, not a gem, nor any coal or iron.

> If you cannot understand that there is something in man which responds to the challenge of this mountain and goes out to meet it, that the struggle is the struggle of life itself upward and forever upward, then you won't see why we go. What we get from this adventure is just sheer joy. And joy is, after all, the end of life. We do not live to eat and make money. We eat and make money to be able to live. That is what life means and what life is for.

Of course, with Venus, there's the joy of exploration and also tons of profits and learning to be had. For example, we could cover the entire planet in giant ads. Think of the CPMs you'd get as people looked out the window on their way to Mercury!