Current world geopolitical situation is vastly different from the age of Empires in past.
US defence industry is an enormous money making machine. Wars are needed to support it. Do not confuse US with USSR. The latter (Empire) broke because of revolutionary ideas and failed economic plans from within.
You guys think that WOT is messy? Check Vietnam then. 58000 US soldiers dead and over 100,000 missing. And I am not even talking about equipment based losses.
Let us face the reality: Iran has got lot more to loose from this war because its infrastructure will be hit hard. And Israeli defensive capabilities are also being underestimated here.
i do agree with some of what you state. But American economy is based on ious and is not sustainable ad finitum