Last time, the showdown over the debt ceiling scared Americans almost as much as Sept. 11 or Pearl Harbor, a top economic adviser to President Obama said.

Now another debt ceiling fight is in prospect, but the level of fear is much lower.

Obama noted recently that “even the mere suggestion of default slowed our economic growth” during the 2011 debt limit debate.

Obama's comments highlight what many analysts see as the real risk to the economy in the looming clash over raising the debt ceiling.

It's not a default on the debt they're worried about. Although a missed interest payment on a Treasury bond would put a dent in economic growth, most analysts expect that Obama and congressional Republicans will strike a deal to raise the limit in time to avert a default.

What concerns analysts is that even the possibility of a debt ceiling fight could hurt investment and dampen consumers’ willingness to spend.

When the Treasury was up against the debt ceiling and running out of resources to pay its bills in July 2011, the president and Congress struck a last-minute deal to raise its borrowing authority. But they were too late to prevent some of the fallout from their brush with a default.

Consumer confidence, as measured by the University of Michigan and Gallup, cratered that month. Uncertainty about policy spiked, according to an index compiled by economists from Stanford and the University of Chicago.

And although both sides said they wanted to use the legislation raising the debt ceiling to cut the debt, the episode cost taxpayers in the end. A Government Accountability Office analysis released the following summer estimated that higher Treasury yields resulting from investors' uncertainty over the government's ability to make interest payments added $1.3 billion in debt costs for 2011. Over the 10-year budget window, the Bipartisan Policy Center found, the costs would total $18.9 billion.

In other words, the 2011 brinkmanship meant slower growth and higher debt.

For a variety of reasons, however, observers are less worried that a showdown would hurt the economy this time around even though the outcome of a default would be just as dire.

One reason is that the public, having seen two major fiscal clashes in the past two years, appears to be less tuned in to the fight. “Perception is, to some extent, reality,” said Stanford economist Nicholas Bloom. He is one of the creators of the Economic Policy Uncertainty index, which gauges the level of the public concern over policy based on an aggregation of news reports.

Bloom said there’s a “roller coaster effect” with debt ceiling fights. “After you’ve gone up and come crashing down twice, the third time isn’t as scary,” even if the risk is real. So far, his index shows little indication that the public is worried about this year’s negotiations.

Other factors that magnified the conflict in 2011 are also missing this time.

In 2011, Standard & Poor’s raised the stakes a few months before the Treasury was due to run out of funds by threatening to downgrade U.S. credit (it then did lower America’s credit rating after the ceiling was raised). This year, the credit ratings agencies have remained silent, even though they still recommend the U.S. lower its debt.

And Congress isn't as narrowly focused on fiscal battles as it has been in the past. Both houses took a month-long recess until early September, meaning little negotiation over the debt took place. Instead, Syria, Obamacare and immigration were the major focuses.

But look for a sharp spike in worries if Congress can't reach an agreement on the debt ceiling and the nation seems heading for a default.