Most American states are required, by law, to balance their budgets. As a result, they do - to a large extent. The United States federal government, however, does not, and has not for many years.
One primary difference, however, between the States and the Federal Government is the method by which a "balanced" budget is declared. For states, there are typically two budgets - the first is an operating budget which only includes those items which are recurring in nature. The second - a capital budget - is for large capital investment costs that are intended to be amortized over many years. For capital expenditures such as bridges, roads, etc..., typically financed by bonds, there is no need to balance this budget.
Now, grant you, many of the largest expenses of the Federal Government (entitlements, salaries for defense and administration, servicing the debt) are not part of the Capital Budgetary Outlay. As such, this alone would not necessarily "balance" the budget - but it would make the numbers look a lot better.
So, why hasn't Congress adopted this technique yet? Considering the sheer number of budget tricks that regularly do get used, there must be some good reason not to adopt this one. What are they?