FACT: THE EMPIRE KICKS BUTT

Take away the Rebellion, and the Empire stands alone in the genre of sci-fi and fantasy universes as the #1Super Power. Look at the other Sci-Fi universes, and even those toughest forces would simply get SPANKED by the Empire. Let's look at some of the others here...

STAR TREK

The Enterprise is half science research platform, and half Love Boat. Okay, yeah, it has some shields... and a PHASER ARRAY. But what is that going to do against a single Imperial Star Destroyer? This goes for even the toughest Klingon warship as well. Here's the deal.

Picture this lonely star system out in the middle of nowhere. Enter the Federation Ship. It scans around, sends a party of Pajama Clad pansies, an "Away Team", to the surface.  Enter the Imperial Star Destroyer.  (You can hear the music can't you?)   The Impstar instantly picks up the signal of the Federation ship and heads over - all ready, looking to kick its butt, just
 because it looks silly.  The Empire has no tolerance for silly.  Aboard the Federation ship, there is a lot of dialog going on about hailing frequencies and channels, and debating upon raising shields.  Aboard the Impstar, Ties are already scrambling,  and the Captain simply says "You may fire when ready."  The Fed's shields would be knocked down after just a couple of   turbo laser hits, the Ties would be ripping up all kinds of havoc.  Tie Pilots saying "Please launch a runabout, please oh please..."  And after just a few seconds, the Fed would be a drifting hulk. Make that several peices of drifting hulks. A couple Lambda class shuttles would launch, landing an actual squad of Troopers armed with BLASTERS and kick some Away Team's nuts.

The Away Team, of course, would consist of high ranking Federation command crew, so after blasting a couple, and the rest surrendering, the real fun would begin.  Prisoners would be taken aboard the Impstar and a Fed Telepath or Empath would go into shock and a coma upon sensing the Imps "feelings".  So the rest of the Away team would get systematically tortured until they reveal the location of the rest of the Federation.   Then they would be tortured some more, just out of principle.  Remember what they did to Han?  Heck, they even liked Han!  He was one of them at one point.   They had the same teachers and what not.

I would give the Federation and the Klingons maybe a month, tops, before the Empire had puppet governments on each of the planets and Regional Governors keeping all the local systems in line. Any trouble spots would get the AT-AT treatment, or an
 orbital-based Turbo Laser bombardment until a Death Star came around and simply popped the whole place like a balloon.   Swarms of Ties would keep the Fed Gunners too busy and an Interdictor Cruiser would keep the Fed ships from leaving the party.  This would make a fun Anime Movie. (Hey, Japan - make it and I will buy it!)

BABYLON 5

Now this hurts, cause I LIKE B5.  But B5 would last 10 minutes at most.   Garibaldi would swoop in with a squadron of Star Furies and get busy against the Ties. But look - while the fighters are mixing it up in a space knife fight, that BIG ASS EVIL DORITO CHIP simply slides past and wails on the B5 itself.    An Imperial Star Destroyer has what? A hundred Turbo Lasers capable of forward fire?  As the Wise Old Owl said "How many licks does it take?" One, ta-who...tthhree.

Okay, in come the Narns and Centari cruisers.  In come some ImpStar Dueces and Lancer Frigates.  We would get a visual treat for a few moments,  but after all the Ties launch like swarms of pissed off Killer Bees, it would all be over but the clean up work. Shadows, too - they could run in on a surprise attack - and then get swatted down like the ugly bugs they are by 700
blasts of heavy T-L fire.  Done.

I think Garibaldi would survive - and end up working with Talon Karde selling slightly vented Star Furies to back water rim colonies.

MIB

Who is next? Lets get funky here - MIBs.  Vader would just simply CHOKE them from the bridge of his Cruiser, turn with flourish of swinging cape with the remark of "All too easy..."  He'd then go back to his THX home entertainment sphere and watch weird Stanley Kubrick films or his soaps thinking "I used to have better hair than that..." and humming to himself old songs like "To all the worlds I've blown before..."

(That's a funny thought - after a planetary assualt, the Stoorm Troopers are marching back to the shuttles singing "M-I-C-K-E-Y... M-O-U-S-E",  like at the end of Full Metal Jacket. Rest in Peace Kubrick, I loved your work...just not as much as Lucas')

UNITED STATES

What about the Empire versus the USA? With President Clinton? Heck, Slick Willie would make a deal so fast it would put Lando to shame. I can just see Clinton Chuckling - "Yeah, you can have all the republicans... if I can just have Leia and Mon Mothma together with a box of Cubans..."

Now that would be scary... Bill Clinton, the Regional Governor in orbit aboard an Impstar Duece, wearing jack boots and a grey imperial uniform.   Of course his only train of thought would be "I wonder if they have a hot tub in this thing, 'cause this baby is AWESOME for cruising for chicks!"