Carney – Uniquely in the solar system, you can grow crops on Mars in cheap inflatable greenhouses. With a 24 hour day/night cycle (no need for expensive artificial light), a carbon dioxide atmosphere (slightly concentrated and pressurized if necessary), and all the elements necessary for agriculture in abundance, Mars can support a permanent human population.
In your dreams.
All the elements necessary for agriculture are not in abundance. Most importantly, there is no nitrogen.
The dead zones on Earths highest mountains are like tropical rain forests compared to Mars.
The soils also appear to contain toxic super oxidizers. Nor will “inflatable greenhouses” achieve the partial pressures of CO2 needed to make plant photosythesis work, nor nitrogen for protein production even if you import your N2 from Earth at 100,000 dollars a pound. And, with 120 DEG below zero nights since the Martian ATM is too thin to retain substantial day-cycle solar heat, the cost of heating your greenhouses is prohibitive even without factoring in the damage regular radiation, intense UV radiation, and damage from irregular solar flares will inflict on plant life.
