Gents,
From the earliest days(1) I have had to deal with the Imperium as a Traveller GM, the Imperium has been nothing but a power sharing agreement among various hi-pop worlds. This idea has served to 'bind' the Imperial Navy's hands IMTU.
While that take on the Imperium began as a way to distance or lessen imperial involvement in the various activities my PCs undertook, later readings by myself in the history of political organization(2) and later revelations in canon seemed to confirm my original suppositions.
IMTU, the Imperial Navy consists of large, powerful warships which are gathered into large, powerful squadrons. For the most part, these squadrons move about, constantly train, and pay little or no attention to merchant traffic, ECMs, or (ahem) piracy unless they are either forced or allowed to do so.
Why? Because in the words of the late, great Freddie Prinz Sr. It's not my job, man.
Sound silly? Mull over the role of the US military in drug traffic interdiction or illegal immigration thanks to the Posse Commitus(sp) act. The USN, USAF, and US Army could patrol the Gulf, Carribean, Mexican border, Sea of Cortez, and Pacific coast tightly enough to prevent ANY unwanted movement of peoples and goods from reaching the US proper. Why doesn't that occur? Because such an effort is not the military's job, man.
Now, I'm not suggesting that the Third Imperium has a 57th Century version of the Posse Commitus(sp) act on the books. What I am suggesting is that either the Imperial Navy's hands are tied by other means or that the Imperial Navy is officially focussed on other missions.
IMTU, the Imperium is ruled by it's Hi-Pop member worlds and they are quite jealous of each other. This dynamic permeates the Imperium from top to bottom.
The major benefit a Hi-Pop world recieves from belonging to the Imperium is that it needn't go through all the trouble of maintaining an empire on it's own resources. It needn't raise huge fleets, huge armies, garrison minor systems, bribe minor systems, and go through all the effort an empire requires solely by itself. The Imperium will do all that and do it wholesale, so the Hi-Pop world gets the benefits of a huge empire 'on the cheap'.
Because they belong to the Imperium in order to 'have' an empire 'on the cheap', the Hi-Pop worlds are always on the lookout for other Hi-Pop worlds exerting 'undue' influence among the 'hoi polloi' of lesser worlds. In other words, no Hi-Pop world will allow another to build an 'empire'; culturally, economically, or otherwise, within the Imperium.
All this means that, for example, the interests of Glisten are very well looked after by the Imperium while the interests of Grote can go hang. If someone or something is bothering Grote and Glisten speaks up for some imperial action to rectify the problem, other Hi-Pop world like Lunion or Aki are going to first think that Glisten is trying to slip a little 'internal' empire building past them and not that Grote actually needs the help. This Hi-Pop 'veto' power on Imperial action means that every Hi-Pop world within a given region can effectively prevent anything from being done for the slimmest, most partisan, or most paranoid of reasons.
Look at the UN and it's Security Council for a real world example of this. When viewed by the purpose stated in it's charter, the UN's only actual success, the intervention in Korea, occurred because the USSR happened to be boycotting Security Council meetings at that time, something it and every other power never did again for obvious reasons. In the case of the Third Imperium, the nobility is the 'security council' and they, while balancing the interests of their worlds and the Imperium, never, ever boycot any security council meetings.
So, Hi-Pop world jealousies and noble orders will bind the hands of the Imperial Navy in all but the most serious of situations. This is not to say that an IN vessel will blithely ignore any and all act of piracy that occurs in front of it. It is to say that IN vessels may not patrol as frequently, or as extensively, or for many of the reasons that we believe they do so. And, it is to say that an IN vessel may be ordered to ignore a trade war act that occurs in front of it.
Any request that the IN go ECM chasing around Grote will have to pass muster from several nearby Hi-Pop worlds and, given their suspicious relationships with each other, getting several nearby Hi-Pop worlds to agree on a spot of IN pirate chasing will take some doing.
This odd view of the Third Imperium is also helped by what Rob Davenport continually points out; The only sectors that we have anything beyond barebones knowledge of are the oddball sectors.
CT and MT only detailed the Marches and Rim of the Classic and Rebellion Eras (DGP's other Grand Survey material is extremely flawed) and T20 lovingly details the Gateway of 993. That's a total of two frontier sectors and a DMZ sector, definitely not common sectors by any stretch of the imagination. What we know of the Imperium, it's member worlds, the roles they play, and the relationships between each in those three sectors cannot be applied to the rest of the Imperium as a whole. The Marches, the Rim, and Gateway are not the Imperium, rather they are the exceptions.
Finally answering Dr. Thomas' question here, I don't see the Imperial Navy as Firefly's Alliance or as Star Wars' Imperial Navy. Instead, I see it as primarily a dynastic force tasked with defending the Imperium from outside threats. Furthermore, the Imperial Navy is closely watched by the Hi-Pop member worlds to see that it is not used by other Hi-Pop member worlds as means of 'internal empire' building. Finally, the Imperial navy is also very closely watched by the Hi-Pop member worlds to ensure it is not used as a tool of coercion against Hi-Pop member worlds.
I know all this is rather torturous thinking, but it the result of my trying to fit together the amoral nature of most Traveller adventures and PC actions with the 'large' but 'uncaring' Imperial Navy description that Traveller seemingly provides.
YMM and should V.
Have fun,
Bill
1 - Yes, I'm ancient enough to have run canonical Traveller campaigns without an Imperium. The ear trumpet, walking frame, and adult incontinence garment should be a clue.
2 - For example, I see the Imperium as operating on a pre-1798 idea of government later labeled 'territorial supremacy' and not the post-1789 'territorial sovereignty' idea that we of 2005 automatically assume when we use the term government.
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