Sure, but it I said, "hey, I found a spare trillion USD in the budget, let's setup a moon base and rotate the crew every 3 months", you would say "ok great, we've proven getting men to the moon and back is a realistic goal". And so it goes. The Russians and the Chinese are both looking at this as something they want to achieve in the next 20 years. It's a proven thing, there's no ifs ands or buts, you can put a man on the moon and bring him home safely.
If something goes horribly wrong on the moon, you can send them back in 4 days express mail style. No big deal.
It's six+ months to get someone home from Mars, and if something happens en route to mars, you just have to wait, there's no early return. If you find out you have terminal brain cancer three days after you leave earth, you have a full year before you can come home for treatment.
But some day we're going to send a man to Mars. Or I will weep for humanity. Hopefully in my lifetime.
At some point you have to prove out that it's possible to sustain human life for 6 months, a year, two years on the surface. That needs to happen sooner rather than later. Would you rather send a man to Mars with a system that has 6 months of flight heritage, or one with 12 years flight heritage? Your astronaut has to live for 2 years on the surface. Do you trust the design with 6 months or 12 years testing without failure? There's very little to no free oxygen on Mars. You have to send an oxygen generator there early on. You couldn't sail very far from shore without a reliable way to carry drinking water for 12 hours, 2, 3 days trip. If you can't provide drinking water for a 6 month trip across the atlantic, you're going to be stuck in Europe. You have to prove out the technology at some point.
If you don't understand the concept of "flight heritage", don't bother replying.