At first blush.
What comes to mind is that Bush-Cheney era casualties have overloaded the system. Their wars, which would cost 20 - 60 billion dollars and last 6 months, are still going on, still costing money, and have left us with casualties which will cost a lot of money for a long, long time.
And none of it was paid for at the time. It's hard to forgive Conservatives for some things, and their lack of interest in paying for their actions is one of them.