As things stand now, we don't have a perfect understanding of how the Earth's core works. Even if we did, though, the amount of energy that would be required to start up a magnetic field on another planet would be, well, astronomical. Keep in mind, the planet weighs 6x10^23 kilograms. A full mole of kilograms is going to take a lot to get spinning.

Will we ever have that much energy at our disposal? That depends on how likely you think humans are to a) annihilate ourselves and b) continue our roughly exponential growth of technology indefinitely.