Elaine Thompson, Associated Press
In this 2009 photo, a customer swipes a MasterCard debit card through a machine while checking-out at a shop in Seattle.

The Great Recession was driven, to a large extent, by runaway consumer spending. To be sure, government had its hand in this by offering incentives and making borrowing easy, and financial institutions compounded bad behavior by expanding portfolios too heavily laden with risk. But millions of consumers bought homes they couldn't afford and got into the destructive habit of satisfying urges by buying now and hoping to pay debts later.

There are reasons to doubt whether Americans have learned lessons from the pain that ensued. Commerce Department data released last week showed that wages and salaries fell 0.1 percent in November, while spending rose 0.1 percent. Most ominous, however, was the news that the nation's personal savings rate fell to 3.5 percent. That is a decline from 5 percent in June and nearly 6 percent in June of 2010.

As a Wall Street Journal report noted, this reduction in savings could make it harder for Americans to withstand more market or political turmoil in 2012. Unfortunately, there are plenty of reasons to fear such turmoil, especially with the European Union still trying to avoid financial disaster in some of its member states, and with Washington unable to decide on a long-term deficit-reduction strategy.

Optimists will point to signs the economy is recovering. Indeed, there are positive indicators afoot, including signs that unemployment is not increasing and that the drop in real estate prices may finally have bottomed out. But if Americans truly are interested in long-term recovery and prosperity, they must not return to their old over-spending ways.

Despite frequent comparisons to the Great Depression, the recent economic downturn did not approach the widespread pain encountered during those days. For many Americans, consumer credit has remained relatively plentiful while prices for consumer goods, adjusted for inflation, remain generally favorable compared to the 1930s. For the unemployed and the underemployed, the past few years have been difficult lessons in austerity. All Americans, however, should have learned the value of accumulating assets and acquiring savings while shunning the fiscal slavery of unsecured debt.

Still, the website creditcards.com reports that Americans held 609.8 million credit cards as of the start of last year and that revolving debt — of which 98 percent is on credit cards — totalled $793.1 billion as of last May. While the percentage of people who say they no longer hold a credit card rose after the start of the most recent recession, those who do have credit cards hold, on average, 3.5 of them.

Credit can be an advantage if used wisely and prudently. Unfortunately, too many Americans have become accustomed to wielding them as plastic swords that slice away the obstacles to the shiny objects of their desires. The nation's declining savings rate, coupled with its increase in consumer spending, is a sign that many have not learned how to live prudently.

That is unwise under any economic conditions, but especially under those as tenuous as the current situation.