I think/know it's entirely possible. And it's not hard.
We already know how to travel in space, set up camp, and exist until supplies are exhausted.
You are overestimating what we are capable of. It is NOT like camping in the woods. Right now, there are hundreds of barriers to long-term spaceflight, and all of them will have to be resolved before we can reasonably expect to make the trip. Solving those problems will aid in the future of mankind. For instance:
1) At this time, food cannot be made that lasts for the time period it would require without taking far too much space (the spacecraft cannot be too large). Creating ways to store healthy food that retains its tastiness for long periods of time will not only aid the space program, but will revolutionize the food industry as we know it and aid in feeding the world.
2) The energy required by this trip is enormous, and enough fuel to travel to Mars, land and return would take a huge amount of storage space and pose a large safety hazard. Some new way to provide energy must be found. More efficient solar panels, for instance. Energy is a worldwide problem and efficient forms of renewable production could change the energy industry across the planet.
3) Over time, the air will become stale. We need better ways of cleaning and converting oxygen.
4) The earth's atmosphere protects us from a vast amount of radiation. Inventing ways to deal with this will create new industries.
And on and on. The great thing - these jobs will be created in the U.S. There will be new industries, new opportunities, new innovations.
Yes, it will be expensive, but in the end, it will be worth every single penny we put into it.
Do I doubt it will aid mankind?
Yes. Exactly my point.
You must understand my point of view if you want it to work.
I understand your point of view. I just don't agree with it at all. Your mindset will have the U.S. slowly degrading into meaninglessness.
I don't give a rip about Mars, and will fight any efforts to spend my money on it.
And I will support all efforts to spend
your money on it. And mine as well.
So...you loose. The odds are low that the effort will return anything at all.
At least, if we didn't already know better, we could imagine meeting martians. But we do know better.
Fortunately, there are people with foresight and knowledge who will do the right thing regardless of people like you. Mars is worth the effort - even more worth the effort if there are no Martians. Game, set and match.