If we assume the existence of technologies that make a Martian colony possible, the same technologies would make asteroid mining even more viable. Now the compl

If we assume the existence of technologies that make a Martian colony possible, the same technologies would make asteroid mining even more viable. Now the complex manufacturing is a whole other set of problems. Unless someone invents a magical 3d printer capable of producing modern CPUs in-situ directly from raw materials, this kind of infrastructure would be the real bottleneck for any Martian self-sustainability dreams.