Smugglers are neutral units, neither they are not Mercenarys. In a mission with the Harkonnens you must protect your outpost, there is a small brown base somewhere and it says ''neutral unit'' means they will not hit you until you hit them. Send few engineers to take the buildings and they will be your allies. NOTE: In a mission with Atreides, Smugglers are allies with mercenaries, as you can capture the smuggler starport. I have made a small description bout allies and shit. Atreides + Freemens Harkonnens + Smugglers Smugglers + Mercenarys Mercenarys + Ordos