The word we keep hearing is “catastrophe.”

“A U.S. Default Seen as Catastrophe, Dwarfing Lehman’s Fall,” screams the headline in Bloomberg Businessweek. “A default would be unprecedented and has the potential to be catastrophic,” says a Treasury Department report issued on Thursday — two weeks before the government is expected to begin running out of cash.

But what does “catastrophic” actually mean in this context? In the summer of 2011, when Republicans refused to raise the debt ceiling unless President Obama caved to their extortionist demands, the same word was bandied about. It scared the political class enough that they kicked the can and avoided a default.

This time around, the need to raise the debt ceiling doesn’t seem to be generating nearly the same concern. Indeed, Tea Party Republicans seem to be almost rooting for the government to default, as if that would somehow bring about the smaller government they so yearn for.

But this is incredibly wrongheaded. A failure to raise the debt ceiling, should it come to that, would likely inflict a different kind of pain than sequestration or even a shutdown of the federal government. It won’t make the government smaller. But it does have the potential to diminish the value of one of America’s greatest assets — the backing of its debt — while throwing the world economy into chaos.