Here are two hypothetical experiments to illustrate my confusion... #1 Two wires are positioned parallel to each other. A current is applied to both wires in the same direction. I would expect the 2 currents to each generate a magnetic field and that the 2 fields would interact to produce a force pulling the wires towered each other. #2 Two electron guns fire electrons 1 by 1 simultaneously along parallel trajectories. Since each electron is going at the same speed there is no relative motion between them, they should behave the same as if they were sitting still. If they were sitting still then they should repel each other. Do I have the correct expectation for each of these experiments? If not, what is my error. If so then the only difference I see between these 2 experiments is the presence or absence of the conductor. Why does this matter?