When wildfires began roaring through Southern California, firefighters had two options: Go on the offensive and attack the flames directly or focus on saving homes and lives.

The wind-driven wildfires were so large and fast-moving that firefighters had no other choice but to defend homes.

"It becomes like a giant chess game, where you're moving the pieces and trying to determine what's the greatest threat potential" for homes and lives, said Glen Newman, spokesman for the Southern Operations Information Center in Riverside.

More than 10,000 firefighters from around the West were at work Tuesday, battling 10 major fires that have burned more than a half-million acres. More than 1,500 homes have burned and another 40,000 were in danger between the Mexican border and Ventura County. Some fire fronts were 60 miles long.

"Never in 40 years have I seen this number of acres burned this rapidly and this number of fires at one time," Newman said.

In most fires, crews have the option of being more aggressive. They can clear brush, cut firebreaks and set backfires, with the goal of starving advancing flames of fuel. But firefighters have had little time to take such measures during this outbreak, and the fierce winds, rugged terrain and housing tracts encroaching onto hillsides conspired to worsen the struggle.

"For 2 days, it's been a totally defensive posture," said Bill Peters of the California Department of Forestry. "We're reacting. We have to go where the homes are threatened. We're not able to cut line."

The presence of thousands of homes — including dozens in the $1 million range — have made things even more challenging.

"You can't burn off the hillside because the homes are there," Peters said.

Even as flames continued to claim lives and property, there seemed to be little second-guessing of firefighting tactics.

U.S. Rep. Duncan Hunter (search), whose home in Alpine, east of San Diego, was destroyed, criticized the lengthy procedure necessary for the state to request aid from military aircraft. Hunter said he requested the use of C-130 firefighting aircraft four days ago, but they only began arriving Tuesday afternoon.

"The military assets come in at the end of the fire ... a strategy of having a slow buildup," he said. "Some changes need to be made."

But he said it would be improper to criticize fire officials' strategies so far.

"I think our people have done a magnificent job," Hunter said. "I think what we have to do right now is win this battle."

San Bernardino National Forest (search) spokeswoman Ruth Wenstrom echoed that sentiment.

"With the limited resources, you set your priorities and rightfully they have been on structure protection. And we have saved literally thousands and thousands of structures — even though we lost so many," Wenstrom said.

In the early days of the fires, water drops were impossible because 45-mph winds and walls of smoke made it too dangerous for aircraft to fly, especially over hillsides studded with power lines, Peters said.

Since then, officials ordered more firefighters and equipment, including water-dropping helicopters from across the region.

The sheer number and size of the fires also has stretched manpower and machinery.

Firefighters carry rations and sleeping bags, and engine crews have credit cards to buy gasoline. Even so, it was a struggle to keep firefighters supplied with everything they need, from lunches to toilet paper.

In San Diego County, home of the deadliest fires, firefighters were so fatigued they were being pulled off the front lines. Some had worked for 48 hours straight.

"What the firefighters are facing is a lack of sleep, a lack of food, a lack of diesel fuel in some cases and a lack of logistical support," said Rich Hawkins, a Forest Service fire chief.

He said the firefighters would leave even though officials predicted that two of the fires would merge and that "blocks of homes" would burn as a result.

"We've never had in my career anything this widespread. It's pushing our people and resources to the breaking point," said Santa Barbara County Fire Department Battalion Chief Ed Rodriguez, a 26-year firefighting veteran, as he watched flames move uphill toward Mount Baldy Village, about 45 miles northeast of Los Angeles.