The field strength of an electromagnetic field decreases with r2. This has two effects:
- small variations in distance create huge changes in the attractive force. This means it's difficult to accurately control e.g. two ships flying towards each other.
- if you want this field to have a measurable effect over the distances used in space, you need a very strong source.
A strong source means a large static charge. The achievable charge is limited by the relative permittivity of the materials involved, if I remember correctly. Too much charge and you get arcing across your insulator to the nearest object with a different potential.
A particle beam won't be useful as a means to project an electromagnetic force over a distance. If the beam hits the target, it's a weapon. If you aim the beam just to the side of the target, beam and target could conceivably attract each other. The result then depends on the relative mass of target and beam. Since the target will be tens of orders of magnitude heavier than the beam, you'll end up using lots of energy to deflect the target a tiny bit.