Mal: The US uses the following logos EVERY DAY, but no one of them is the "Single Official Symbol":
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- The Great Seal of the United States</font>
- The Stars and Stripes</font>
- The Starry Jack (Blue field with 50 white stars. Officially, this is supposed to fly off the jackstaff, but usually isn't, with the stars and stripes used instead. But it is the official Jack of the US. LPM, 1986 edition)</font>
- The Star and Bar (Aircraft insignia)</font>
- The U.S. pins (Army/AF)</font>
- The Shield Barry of 13 Gules and Argent a Chief Az semi of mullets of 5 points 7 then 6. (The Arms of the United States)</font>
- An Eagle Displayed proper bearing upon its chest the Arms of the United states maintaining in dexter talon three or 5 arrows, and in sinister talon a Fascio (The axe with the bundle of sticks). (The Armorial Achievement of the United States.)</font>
Now, I've only seen the jack on a couple of craft, but I have seen it in use. The Armory is used in some surprising places: All Army Officers wear the Achievement on their hat crests for the dress/service cap. Coast Guard Chiefs have the Arms on their Anchors.
The Great Seal is on Every $1 bill.
The Flag is in every Military Unit HQ not deployed, and most of the deployed ones, as well as almost all classrooms.
The US Logo is on US Army Dress Uniforms, and last I checked, USAF as well.
The Star & Bar is used on almost every US Military Aircraft.
Which one is "THE" symbol of the US?
Likewise, the UK has their Union "Jack" (At one point it was the jack, while the navy used the jack on a red flag like the US uses the stars over the stripes; teh Aussie and NZ flags reflect this use as well), The Crown, the Queen's "Official Sillouette" (as seen on UK, Aussie, NZ, Canadian, and other commonwealth coins and stamps), The Royal Arms, and a the Red, white and Blue "Target" on the aircraft.
Which one is "The" symbol of the UK? To the outsider, probably the Union Jack, but it is more properly a symbol of being part of the Empire at some point... It's part of the Hawaiian State Flag, too!
The Queen's sillouette is going to change sometime... Her Royal Majesty isn't Immortal.
The Arms probably won't change, but have in the past.
The Crown used varies slightly in various uses, but is similar enough to other in-use crown insignias that it's not QUITE distinctive at the sizes used.
So, why would an interstellar empire be any more likely to have a "Single" ONE true emblem? They probably would not. They might have one that is their primary one, or even one that is used as a common part of all their official insignia, but a single one is a political unification propaganda tool, rather than "Normal" state.
