Why the sudden ubiquity of deficit scare stories? It isn’t being driven by any actual news. It has been obvious for at least a year that the U.S. government would face an extended period of large deficits, and projections of those deficits haven’t changed much since last summer. Yet the drumbeat of dire fiscal warnings has grown vastly louder.

To me — and I’m not alone in this — the sudden outbreak of deficit hysteria brings back memories of the groupthink that took hold during the run-up to the Iraq war. Now, as then, dubious allegations, not backed by hard evidence, are being reported as if they have been established beyond a shadow of a doubt. Now, as then, much of the political and media establishments have bought into the notion that we must take drastic action quickly, even though there hasn’t been any new information to justify this sudden urgency. Now, as then, those who challenge the prevailing narrative, no matter how strong their case and no matter how solid their background, are being marginalized.

And fear-mongering on the deficit may end up doing as much harm as the fear-mongering on weapons of mass destruction.