My son and I recently watched all six Star Wars movies together over a few days. It is really great when you share something you really enjoy. But something hit me while watching...The Empire only lasted about 30 years.
Was it that Vader threw The Emperor down the shaft of the 2nd Death Star? Was it the loss of so many men on the two Moon sized battle stations. I think not. I believe, like the Soviet Union the Galactic Empire fell apart due to dramatic overspending and a collapsed economy.
NASA's budget in 2007 was $16.8 Billion dollars and they can barely get the Shuttle to blast off. Even with using slave Ewok labor you still have materials and overhead, not to mention a massive military buildup and budget deficit! It would take a budget in the quintillions! The Emperor was just too focused on wiping out the rebels.
People think that he removed the Galactic Senate just because he didn't want to ask their permission to crush the Rebels. I believe that it had much more to due with the funding bills that they wouldn't pass.
Imagine the debate on the Senate floor when a Second Death Star came up to be appropriated. I am sure it was in the "Really Black Ops" budget, but some one had to ask the question, "If these are so strong...why do we need two?" Then the Emperor would have to explain that in the first design, they ran out of time and forgot to weld over a small hatch...oh, about the size of a womp rat. Probably no biggie, but just in case...
That was probably the straw that broke the dewback. The Senates got to go.
So let this be a lesson to you; Watch your budget and be careful with your spending or Vader will toss you overboard!