NEW YORK (CNN/Money) - No question, Americans' thoughts turned to family, friends and the home after last September's terrorist attacks.

Many on Wall Street believe it was this so-called "cocooning" effect that prompted the quick rebound in sales at the nation's retailers, particularly among home building and home furnishings companies, and at consumer electronics and discount chains.

A year later, consumers have maxed out their credit cards and become more jittery about their jobs and the economy. Such concerns have begun to overshadow the drive to refurbish and upgrade on the home front.

Even discount chains, whose sales soared in the months after the attacks, are now feeling the effects of sluggish consumer spending.

Last week, Wal-Mart, Target and a host of other retail chains reported an anemic 1.6 percent increase in August sales at stores open at least a year compared with the same period a year ago, according to the Bank of Tokyo-Mitsubishi, which tracks such data. That's the worst monthly performance since last September, Michael Niemira, BTM's chief economist, noted.

"Obviously it was not a good month for retailers in August," Niemira said. "I suspect it's the economy finally catching up with retailers."

"We are really seeing a cautious consumer who is cutting back on discretionary spending," said Kurt Barnard, president of Barnard's Retail Consulting.

Indeed, Merrill Lynch, which cut its ratings Aug. 27 on several retailers including Nordstrom (JWN: Research, Estimates) and Family Dollar, said the "bunker mentality" that led consumers to spend more on home-related items after Sept. 11 is now waning.

And now discount chains such as Wal-Mart (WMT: Research, Estimates) and Target (TGT: Research, Estimates) have reported monthly sales below their own forecasts, even though they've continued to outpace their higher-priced competitors. Department stores and many specialty chains, on the other hand, especially clothing retailers, are struggling with sales declines.

The summer's sluggish sales are a marked contrast to the weeks and months immediately following the September attacks. Revenue at home-related retailers in particular soared compared with other types of stores.

"After Sept. 11, especially immediately afterward, people were very fearful. They began counting their blessings," said Audrey Guskey, a consumer trends expert and marketing professor at Duquesne University. "They realized they wanted to take advantage of the good things they had at home, so they devoted resources to that."

Sales at home building and home furnishings companies, along with consumer electronics and discount chains, were higher than at other retail segments in the fourth quarter following the attacks, according to figures compiled by tracking firm First Call. And those categories continued to lead in the first half of 2002.

"A lot of food items, basic staples, canned goods, food, milk and bread were sold," said Wal-Mart spokesman Tom Williams. The world's biggest retailer sold lots of gas cans, radio and television antennas, flags and even ammunition sold well, he added.

That translated into sales, which in turn translated into a general boost for retail stocks. Shares of Home Depot (HD: Research, Estimates), the world's largest home improvement retailer, jumped 44 percent between Sept. 17, 2001 and Feb. 25. Shares of its better-performing rival Lowe's Inc. (LOW: Research, Estimates), soared 69 percent between September and May. Meanwhile, shares of Pier 1 Imports (PIR: Research, Estimates), a home furnishings retailer, jumped 150 percent to $22.47 on June 19 from $8.96 last Sept. 17. In the discount segment, Wal-Mart (WMT: Research, Estimates) saw its shares rise 33.5 percent between September and June while competitor Target Corp.'s (TGT: Research, Estimates) shares jumped 52 percent.

Best Buy Inc. (BBY: Research, Estimates) the top consumer electronics retailer, saw its stock jump 67 percent between September and March.

But now practical concerns about job security are beginning to weigh heavily on consumers. The unemployment rate climbed as high as 6 percent during the summer. Predictably sales of summer-related items began to slacken after the July 4th holiday.

This is prompting some analysts to wonder just how much of a part cocooning actually played in boosting sales earlier in the year. A record 11 interest rate cuts last year helped drive home sales, refinancings and home improvements, which have all contributed to brisk sales of home-related items, analysts said.

"Cocooning has become a cliché kind of thing," said Donald Trott, a retail analyst at Jefferies & Co. "Home furnishings has been strong and home improvement has been strong, but the stimulus hasn't been 9/11. The stimulus has been this rise in residential real estate."

Regardless of whether it was cocooning or a home-buying binge, things have cooled considerably.

Last week's chain store sales report with its minuscule 1.6 percent sales growth from a year ago shows a more careful consumer. Though auto and home sales remain strong, Americans are shopping less. Even Wal-Mart and Target, which have steadily grabbed market share from other types of chains in the wobbly economy, missed their sales forecasts.

And as a result, retail stocks are sputtering. Home Depot's stock is down about 36 percent since February, and Lowe's shares are down about 8 percent since May. Shares of Pier 1 Imports, Wal-Mart, Target are all slightly lower, and Best Buy's shares have been cut in half.

If the sales decline continues, analysts caution that the upcoming holiday season, the most critical of the year for retailers, could be marked by heavy discounting and sluggish sales, all of which cuts into earnings.

"We kind of expected this. Consumers are probably a little strained due to a bad economy and a bad stock market," said Scott Krugman, a spokesman for the National Retail Federation, one of the nation's largest retail organizations. "I think that as long as the weather is warm, there's really no hurry to buy fall clothes."

The NRF expects to publish its sales forecast for the 2002 holiday season on Sept. 16. Whether cooler weather and improved economic data brings consumers back to the stores remains to be seen. But the recent sales data shows Americans have apparently shed their Sept. 11 cocoons.