The biggest disruptions are less visible — the workers going without pay, the patients turned away from research clinics, and so on.
The government is likely to shut down on Tuesday. Here's our comprehensive explainer on what will happen next.
Which parts of the government close down, which parts stay open, and how the economy could be affected.
To keep his budget promises, Mitt Romney would have to cut all programs that aren't Medicare, Social Security or defense by an average of 40 percent in 2016 and 57 percent in 2022. This will never happen.