mike wightman
SOC-14 10K
Except when it doesn't...I don't know about that. As I said above, the Imperium takes a hands off approach to world politics.
The Imperium enforces its Rules of War (see Striker Book 2 pages 43-44 for the best version) when it has something to gain from doing so. Remember that we are dealing with a sector a long way form the remote central government, where local planets have autonomy.
There you have the real reasons for intervention:Only when local conflicts threaten either the security or the economy of the area do lmperial forces take an active hand, and then it is with speed and overwhelming force.
security - the outcome of a conflict may lead to a planet leaving the Imperium
economy - the conflict is interrupting the tax take.
mercs can be hired by:
the Imperium itself (see FFW)
subsector dukes
planetary governments
rival planetary governments
rebels against planetary governments
megacorporations
anyone with the credits...
On a TL13+ battlefield I don't see an issue with nukes and chemical weapons, but they do provide a convenient excuse for intervention if one is needed by the local IN captain to send in the Imperial Star Marines to settle things...I can see them stepping in if the merc company uses nukes or some other weapon that the Empire has outlawed. Maybe chemical weapons.
That would depend upon how much influence the world government has on the local Imperial nobility and IN and if they petition for the intervention, no taxes until the mercs heads are on spikes...But, if the merc company destroyed some local religious shrines? I don't think the Empire would interfere.
If only there was evidence for this sort of thing happening...Or, what if the merc company completes a coup against its own employer, setting itself up as the local ruler. Again...I'm not sure if the Empire would go in and set things right.
oh, wait a second
Lunion subsector of the Spinward Marches. Note it doesn't even get an amber zone designation...The government on Quiru is a military junta which is the result of a mercenary operation. Imperial force has not yet been brought to bear.