I'm sorry but that is very short sited on your part.
There are several ways that Mars "theoretically" could be made habitable for human life. I don't have the time to relate all of them, but for starters we can thicken the atmosphere by melting the caps or by using comets and slamming them purposefully into the planet bringing water an CO2 to the atmosphere. We can also bioengineer plants to subsist on the current and later thickened atmosphere to produce oxygen.
With current technology we have the basic know how it is merely a matter of scale and developing the engineering to do it.
Even if economic or feasible it still does not change the fact that without heat,life cannot exist.Heat comes from the Sun or the transition of matter from one form to another.On Mars the sun cannot provide adequate heat because of the distance so energy must be expended to create it.
This idea that Mars once had life is just another way that huminists attempt to push creation off the table.
Excuse me, but the reason given by most scientists as to why Mars lost its atmosphere is because it lost its magnetic core because the core cooled off. This caused the loss of atmosphere. If this is true, then bringing in water and co2 is not going to help. Mars still does not have a molten core, iron to be exact, that it needs to have magnetism. Without it, we cannot hope to terra form it. This problem would have to be solved first or any atmosphere we bring in will be lost to space just as the original was.
Nuke Mars For its own good!
Now that the soviets are gone, we have all of these nuclear weapons lying around. Many are still attached to rockets capable of escape velocity. I propose that 90% of these be launched to detonate on the Martian icecap. There is a lot of water frozen on mars, and the energy of a colossal nuclear explosion will suspend a haze of water vapor and dust into the martian atmosphere. This will create a greenhouse effect, warming the planet, melting more ice, and causing more atmospheric haze. As the Martian atmosphere becomes warmer and wetter, several more rockets with varied photosynthetic bacteria should be sent to Mars as well. Natural selection and mutation (no doubt fueled by residual radiaoactivity) should allow these robust critters to adapt and begin putting out an oxygen atmosphere. I am a little concerned about available carbon but I understand the Mars does have some areas of carbon dioxide ice, which could be freed up for use by the remaining 10% of the nuclear missiles.
I see this program as akin to planting a seed from which will grow a wondrous fruit-bearing tree. In a few hundred years out descendants will thank us for beating our swords into plowshares and planting the seeds of a beautiful new world for them.
So anyway, there was this martian spacecraft that landed in this farmers field. The farmer and his wife were very frightened as it landed about 40 yards from their back porch. Suddenly the door to the spacecraft slowly opened and 2 seemingly human like creatures walk out and up to the porch where the farmer and his wife were watching. The male martian raised his right hand in a sign of peace and then spoke and said, "We are from Mars and come in peace on a scientific mission." So after a few moments the farmer invited the two aliens into the house whereupon the martian and his female martian companion spoke and asked questions about the earth, entertainment, politics, oceans, continents,and every conceivable subjectmatter. Then the subject of reproduction came up and the martian asked how humans reproduce. So the farmer explaind the conjugal act. The martian said "Well, that is very similar to how it is done on mars." He then propositioned the farmer to allow him to experience the act with a human and let his female martian companion experience the act with him. Well the farmer got somewhat riled up at this proposition, saying " We don't act like that here on the earth." The martian explained it was for scientific endeavors and slowly convinced the farmer to consent. So the male martian and the farmers wife retired to the barn. She was somewhat confused when he disrobed and saw a tiny vestigeal member presented. She laughed and said "That certainly won't work." The martian said why. She said because, well, not want to hurt his feelings, said well, its too small. So the martian reached up to his right ear and twisted it. At that instant his pecker emerged about 9 inches and looked like a pencil. The farmers wife said, well, thats better, but it still won't work. The martian said "Why"? She said the diameter,...its, its too skinny. Whereupon the martian took his left hand and twisted his left ear. Suddenly the martins member looked like a hot house cucumber. She said, "That will work." Once the conjugation was completed, they returned to the house and there was a somewhat perturbed farmer washing the coffee cups. He said to his wife, "Well, how did it go?" She said "Great, really great." The farmer was fuming. She said to her husband, "How was it for you?" He said, "It was awful." The wife asked "Why?". The farmer replied curtly, "The bitch kept trying to rip off my ears."...............................Uh Oh...I thought it said "Wife Swapping on Mars"