[Ryzorian]

The thing about secrets is that the more people who know about it, the less it's a secret. You understand how many people it would take to build something like that? Even with droids doing some of the heavy work, you would still have large numbers of civilian contractors because there weren't that many droids around then, Palpatine had a large number of them decommissioned after the "Clone wars".

The only reason no one "knew" anything about it was due to the Dark side clouding everything, like a veil. The monster could be in plain sight, but the veil makes people fail to see what is really there..

Besides, the empire had a massive fleet of Star Destroyers and Super Star Destroyers, nobody was hideing those in some "emperial" area 51, and they could destroy planets as well. The DS's big asset was One Shot, One kill. Though I think the money spent would have been better placed on more Star Destroyers, because they can get the job done and you can show more imperial influence via ports of call. Plus the DS was too much of the "eggs all in one basket" type of thing.

Another thing people miss is that not everyone thought the "empire" was a bad thing, or even the bad guy. Billions of folks lived very well within the empire, same as Roman citizens did dureing Pax Romana.

That's the true irony of war, every nation has stories of classic struggles between good and evil, with good being triumphant. In war everyone think's thier the good guy and the other side the bad guy. The bad guys loose right? It's why many wars last well beyond the point of no return because nobody is the "bad guy".