This book convinced me that, unless we can find a way to circumvent the speed of light, we will never have interplanetary, let alone interstellar, travel.
I think that’s a crux of it. I don’t disagree with a single thing @Stranger_On_A_Train said. However, I reckon It could be done in maybe 5 to 10 years if the only objective is to get at least one person to the surface alive, and if the mission was prepared to expend lives all along the way, and if the return (or indeed prolonged surface survival) of the mission is of no matter.
Nobody is likely to do that of course - indeed there is an argument to say that wouldn’t be ‘putting humans on Mars’ as much as ‘putting lab rats on mars, where the rats happen to be of species Homo sapiens’
That’s true, but Apollo was basically a publicity stunt. That’s why it was abandoned so quickly. I am not sure what the point of even a moon base would be. And Mars? Even less so.
The point of a(n as closely as possible) self-sustaining colony on Mars is to get a breeding population of humanity several months travel time away from nuts with nukes. I can’t find the quote but some visionary once said words to the effect that atomic power would not only make spaceflight possible, it would make it necessary.