Okay, in inertial reference frames, two particles with the same charge will always repel each other. Even if they were moving in parallel at high speeds, and thus producing magnetic fields, special relativity would come in and balance the forces from the electric and magnetic fields so that there would be a net repulsion. But suppose that two particles of the same charge were moving parallel to each other in a circular motion. Is it possible there could be a net attraction from the induced magnetic fields? More generally, is it true in general that it is always impossible for two particles of the same charge to have a net attraction?