The bad news coming out of Detroit this week was not unexpected, but it clearly defines the serious challenges facing U.S. automakers.

September sales for GM and Ford were down 24 percent and 20 percent respectively. Vehicles sales fell after strong summer sales generated by the employee pricing promotion launched by General Motors and later copied by Ford and DaimlerChrysler.

Designed to stimulate sales following a slower-than-expected first half of the year, the employee pricing incentive program was successful in posting strong summer sales numbers and clearing dealer inventory.

But the big summer push also clearly cannibalized fall sales by pulling potential sales from the fall and even winter into the summer months.

If it were only a slow fourth quarter due to the summer promotion, Detroit would hae little to be worried about. But Detroit's troubles extend well beyond the dependence on bigger and bigger financial incentitves.

Hurricanes Katrina, Rita and the continued gains of Asian automakers have put Detroit's so-called Big Three into serious trouble.

It hasn't helped that Wall Street lowered their bonds to junk bond status.

Hurricane damage in teh Gulf Coast caused shutdowns oil refineries and produced a dramatic spike in fuel costs. Seeing gasoline hovering around $3 a gallon, has many drivers are paying more attention to miles-per-gallon ratings than to 0-60 mph figures. And that doesn't bode well for Detroit's bread-and-butter products - SUVs and light trucks.

With a disproportionate share of Detroit automakers ' profits coming from SUVs and trucks, the apparent acceleration of the shift away from low-mileage SUVs to more fuel efficient cross-over vehicles and traditional sends is coming sooner than expected.

Meanwhile, the Japanese carmakers are well positioned to receive the drivers looking to turn in their gas-guzzling SUV or truck.

September sales figures for Toyota, Honda and Nissan all increased by double-digit percentages.

DaimlerChrysler fell in between the other U.S. automakers and Asian car companies, posting a 4 percent increase in September.

Writing in Car and Driver magazine, columnist Brock Yates suggests Detroit automakers are in a fight for their lives. In 1999, domestic automakers supplied 62 percent of the U.S. market. By 2004, Detroit's market share had slipped to 53 percent, and will soon drift below 50 percent.

During the same time period, Asian cars grew their share of the market to 38 percent.

Yates points out that those figures are actually worse than they appear because the Asian imports are strongest in the states with the greatest population growth. Those dynamic markets, with more of the younger and Hispanic car buyers, favor Asian imports to a greater degree than the rest of the country.

The Japanese have set the standard in terms of quality, innovation and value. In recent years, the South Korean manufacturers have dramatically improved their product. And on the horizon, warns Yates, is China, where a billion-driver domestic market will provide a launching pad for eventual export to the United States.

Domestic carmakers can no longer rely on the truck and SUV market - not with gas unlikely to drop from its current levels anytime soon. To survive, Yates suggests that domestic automakers must return to the car market with products that are superior in styling, engineering, fuel efficiency and reliability to the Asian imports. The survival of the so-called Big Three automakers will require, according to Yates, "ugly confrontations with United Auto Workers and the corporate retirees."

The road ahead for U.S. carmakers looks every bit as rocky as the path followed over the past decade by the domestic steel industry and, more recently, the airline industry. Wrenching changes lie ahead if Detroit automakers expect to survive in anything close to their current size and presence.

The demise of the domestic automobile industry was predicted as early as the mid-1970s, during the initial wave of the Japanese invasion. It's taken 25 years and a jump in fuel costs, but the day of reckoning for Detroit has finally arrived.