To successfully terraform Mars, the atmosphere would need to be raised enough so that humans could walk around without spacesuits. But although tripling the Red Planet's atmospheric pressure might sound like a lot, it's only one-fiftieth of the CO2 necessary to make the atmosphere habitable to Earth creatures.
Terraforming or terraformation is the hypothetical process of deliberately modifying the atmosphere, temperature, surface topography or ecology of a planet, moon, or other body to be similar to the environment of Earth to make it habitable by Earth-like life. HOW WE ARE USING TERRAFORMING ON MARS: Scientists themselves have proposed terraforming to enable the long-term colonization of Mars. A solution common to both groups is to release carbon dioxide gas trapped in the Martian surface to thicken the atmosphere and act as a blanket to warm the planet.
Yes, because one system would have to much power and be able to have full control and do whatever they want. This would lead to corruption and tyranny.