The original LBB:4 mercenary set the scene for the internal conflicts within the Imperium, the squabbles between rival planetary systems, local corporations or even nobility. I would argue that it didn't go into enough detail of Imperial vs peer adversary... and the rules were still a little generic.
"Traveller assumes a remote centralized government (referred to in this volume as the Imperium), possessed of great industrial and technological might, but unable, due to the sheer distances and travel times involved, to exert total control at all levels everywhere within its star-spanning realm. On the frontiers, extensive home rule provisions allow planetary populations to choose their own forms of government, raise and maintain armed forces for local security,* pass and enforce laws governing local conduct, and regulate (within limits) commerce. Defense of the frontier is mostly provided by local indigenous forces, stiffened by scattered lmperial naval bases manned by small but extremely sophisticated forces.** Conflicting local interests often settle their differences by force of arms, with lmperial forces looking quietly the other way, unable to effectively intervene as a police force in any but the most wide-spread of conflicts without jeopardizing their primary mission of the defense of the realm***. 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.****
The combat environment of the frontier, then is one of small, short, limited wars.***** Both sides must carefully balance the considerations of how much force is required to win a conflict with how much force is likely to trigger lmperial intervention. At the same time, both belligerents will generally be working with relatively small populations, with only a negligible number of combat experienced veterans. In this environment, the professional soldier will find constant employment. Small, poor states faced with invasion or encroachment will hire professional soldiers as cadres to drill and lead their citizen militias.****** Larger states will be able to afford to hire and equip complete mercenary contingents as strikers, or spearhead troops. Small commando units will be in demand as industrial espionage is waged between mega-corporations virtually nations unto themselves.******* In addition, the hired soldier will always be in demand as security or bodyguard troops, as force remains the only true protection against force. The Golden Age of the Mercenary will have arrived."
*Local forces, equipped with whatever can be locally supplied or bought in.
**This is the misleading part, this really refers to internal deefence, ie domestic threats, rather than facing off against a rival empire (the setting was still being detailed at this point)
***there we have it, the primary role of the Imperial armed forces is defence of the realm, again the missing words are from external peer level threats
**** the Imperial Army does not get involved often in local disputes, but when it does it ends it
*****this is the theme that the book is portraying, the conflicts within the Imperium that the PC scale of things may lead to adventure
******this means that despite what you may think, world vs world does happen, it isn't all conflict on balkanised worlds
*******the concept of corporate wars or trade wars...
the only thing that is missing is rival subsector dukes loaning their huscarls to settle disputes... but I don't think the setting had been developed to that extent yet.
