Jared Bernstein posted this chart the other day, and if you missed it, it’s worth keeping in mind as the debt debate continues.

Republicans assume, and expect everyone else to assume, that the government is bringing in plenty of money to meet its needs. Sen. Jim DeMint (R-S.C.) went so far as to tell a national television audience this week, “Four of the last five years, we’ve had record levels of revenue.”

It’s important to understand how very wrong Republicans are about this. Federal revenues have dropped to 15% — a 50-year low. To bring the federal budget closer to balance, we’d expect to see this number around 19%. Given the fact that we’re fighting at least two wars and dealing with the aftermath of a brutal recession, all while worrying about deficit reduction, the fact that the right sees 15% as too high is insane.

Bernstein explained:

There’s obviously much more to this analysis then a couple of lines on a graph, but the history of structural (versus cyclical) deficits in recent decades is that they are largely the result of cutting revenues rather than raising spending (and visa-versa-remember Clinton’s budget surpluses).

That doesn’t imply that spending shouldn’t be on the table in the budget talks — though the real pressures come in the future, through health care — whacking food stamps, education, and so on is just plain mean. But it’s awfully hard to look at this graph and see support for that Republican mantra.

That’s an exceedingly polite way of saying, “They’re completely full of it.”

Remember this the next time you hear, “We don’t have a revenue problem.” In reality, we obviousy have a revenue problem — if the goal is to reduce the deficit.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.