more depressing is that a space elevator might never see the day, since the material required for it is difficult to make and even if it did exist, I have no i

more depressing is that a space elevator might never see the day, since the material required for it is difficult to make and even if it did exist, I have no idea how that thing would be put in place if I remember, in the mars trilogy, it's assembled in high altitude, low gravity, and then put in place? but gravity is lower on mars so rockets work better? anyway, for earth, assembling a space elevator in space, meaning putting tough cable in orbit, would require so many launches and would emit a lot of CO2 in the process. also the cable might be progressively thicker starting maybe at 1/3 of the distance, to bear the entire weight of the lower cable that is the most affected by gravity, while the rest of the cable would have a progressively centrifugal force away from earth to compensate, so maybe the cable would not need to be thick everywhere. maybe that question was already asked