As the OP suggests, the US is a de facto empire, with military bases and "client states" all over the world. Also, as suggested, the US is many trillions in debt with no clear or easy way to get back into the black.
The old-fashioned way that empires used to deal with this problem was to rape, pillage, and burn. In other words, the empire was financed by successful military campaigns against various tribes or nations that posed threats and had resources such as women, gold, oil, timber, land, water or other valuable resources from which the empire could prosper.
The trouble with the US is, although we have been almost continually at war since 1945, there have been no clear victories and several costly setbacks, and have not served the righteous purpose (for an empire) of enriching the central treasury and securing a one-way inflow of lesser nations' resources.
Accordingly, it seems clear and obvious that it is well past time for the US to either ditch being an empire, or "get with the program" and start winning our wars for a change. We need to win these wars in order to restore a permanent source of tribute and put the empire back on a healthy footing.
Assuming we want to continue as an empire, I suggest we mount an immediate campaign against an easy, nearby mug with lots of cash and valuable resources. This is none other than Canada. Easily securing Canadian gold, oil, uranium, rare-earth minerals, timber, water, fisheries and agriculture for the higher use and aggrandizement of the empire should be a no-brainer, even for our PTSD damaged trigger-pullers and their eggheaded generals like Patraeus.
All we need now is an aggressive, visionary leader like Newt, Mitt, or Rick with a big, hairy sack who will go out and lead the charge.
Facetiously submitted,
Steve