Building the Death Star from Star Wars is a highly questionable choice on multiple levels; it’s a giant weapons platform designed to commit war crimes that also violates the laws of physics. And, it turns out, not securing the thing properly would deliver a more decisive blow than any strike team from Yavin ever could.
Zachary Feinstein, a financial engineering professor at St. Louis’ Washington University, used some rough estimates to figure out the price tag of the Death Star. The cost? $193 quintillion in 2012 dollars. Yes, as in 10 to the 18th power. To give you an idea of how much that is, this means the GDP of the Empire has to be $4.6 sextillion a year just to make building this white elephant a reasonable proposition. Just for a measure of scale here, in 2013, the Earth’s total GDP was $75.6 trillion.
It gets better, though: Using what we know of how the galactic economy works, Feinstein points out that due to nationalization, the banking sector would have been heavily invested in the construction and possible profit from the Death Star. So, after the events of the original trilogy, between depreciation and costs, the Empire would have to eat a $515 quintillion turd sandwich. And this is the best possible scenario, assuming the Emperor had kept other debt under control, that the first Death Star was half paid for, and that Emperor Palpatine could borrow at a 0% interest rate. That last one we find credible because, come on, he’s a tyrant, but everything else? Nah. Why wouldn’t Palpatine borrow like crazy? Who’s going to collect?
So, essentially, after Return of the Jedi, there was a massive, galaxy-wide economic collapse, which would explain why the Empire fragmented and why the rebellion had trouble taking over. It also explains why the First Order is hollowing out a planet for its giant boondoggle of a weapons platform; even an excavation of that scale has to be cheaper.
(Via Pop Sci)