I just think it's safer to try the Moon and then go to Mars. If anything goes wrong in Mars, anything we didn't calculate since we haven't officially announced to have done this before so I'm sure there would be surprises. I think it's an unnecessary risk, we could simply lose communication and we'd never know about the crew again because they are too far. I can understand wanting to settle where the gravity is similar to that on Earth, but at the very least there should be a station in Mars to recharge, for supplies, so that every time something goes wrong we don't need to ship stuff/people out but help can be found by landing the moon instead.