[Fyron]

They meet at trading stations outside the mine field. Their cargos are sold/unloaded there and they get money or have whatever they were trading for transfered to them, end of story. Or perhaps their trade vessels are escorted through the fields, and the mines change positions every so often, based on secret calculations which vary over time so as to eliminate the possibility of mapping the sequences. Warships certainly wouldn't be allowed near the planets... And if the local defense forces detect a massive fleet heading towards the planet, all civilian ships would be denied access and the mine fields would be remapped. There are many possibilities. Just because we sign a trade treaty doesn't mean I have to give your ships free reign to go wherever they want to... Yes, technically the game allows this silliness, but it should not. SE5 is going to have the ability to customize every treaty you sign, so we can trade and not give free access...