IF China or Iran threatened our national credit rating and tried to drive up our interest rates, or if they sought to damage our education system, we would erupt in outrage.

Well, wake up to the national security threat. Only it’s not coming from abroad, but from our own domestic extremists.

We tend to think of national security narrowly as the risk of a military or terrorist attack. But national security is about protecting our people and our national strength — and the blunt truth is that the biggest threat to America’s national security this summer doesn’t come from China, Iran or any other foreign power. It comes from budget machinations, and budget maniacs, at home.

House Republicans start from a legitimate concern about rising long-term debt. Politicians are usually focused only on short-term issues, so it would be commendable to see the Tea Party wing of the Republican Party seriously focused on containing long-term debt. But on this issue, many House Republicans aren’t serious, they’re just obsessive in a destructive way. The upshot is that in their effort to protect the American economy from debt, some of them are willing to drag it over the cliff of default.