The attackers would go underground, taking no credit, then re-emerge on Yom Kippur at a West Los Angeles synagogue and shoot as many people as they could.
More attacks were planned as vengeance for the "oppression" of Muslims by the U.S. military in Afghanistan, Iraq and Guantanamo Bay. None happened, according to state and federal authorities, because agents swiftly discovered a string of gas-station robberies were financing the plot, allegedly hatched by homegrown criminals who converted to Islam in New Folsom prison.
"Make no mistake about it, we dodged a bullet here. Perhaps many bullets," said Los Angeles police Chief William Bratton.
"There's no question that we prevented a terrorist attack," said Matthew Bettenhausen, California's homeland-security chief. "What could have been a catastrophic, multitargeted style of attack ended in arrests."
Yet police learned of the plot largely thanks to the three men's missteps and bad luck: Lacking money for weapons, they turned to robbing 11 mom-and-pop convenience stores and gas stations, guaranteeing police were looking for them months before the attacks.
One would-be jihadist dropped his cell phone during a robbery, and police trailed the men to the next robbery and arrested them. A search of one man's apartment turned up bulletproof vests, knives, an order for an AR-15 assault rifle, an apparent target list and literature justifying the killing of infidels.
What counterterror investigators wonder is, will the next plotters be so inept or indiscreet? Or as in the case of al-Qaida, so bent on mounting attacks more spectacular than Sept. 11 that the chances of detection soar?
No one knows. But while law-enforcement officials agree that California and the nation are vastly better at detecting attacks, they say someday a major attack will succeed inside the United States.
Last week, in its latest National Strategy for Combating Terrorism, the White House echoed that assessment, stating that "while America is safer, we are not yet safe. The enemy remains determined, and we face serious challenges at home and abroad."
Al-Qaida hijackers succeeded in collapsing the World Trade Center in 2001, according to the 9/11 Commission, because of a "lack of imagination" in the U.S. government and an inability to connect the dots. Since then, law enforcement and intelligence agencies have built a huge, multilayered machine for imagining plots, swapping information and looking for dots to connect.
"We are reaching out and working well with virtually every sector," said David Ego, assistant special agent in charge of counterterrorism for the FBI's San Francisco Division. "We're scrubbing not only foreign intelligence but domestically collected intelligence. We're trying to predict trends, identify threats and quickly adapt. We're doing a heck of a lot better."
Three FBI-led joint terrorism task forces work the Bay Area, with dozens of officers detailed from big-city police departments and given national security clearances. Smaller and outlying towns have named some 75 terrorism liaison officers. Federal agents and private companies meet in special working groups on everything from tall buildings and data sharing to refineries.
Nationwide, the FBI has cultivated ties to U.S. Muslims, to catch wind of any newcomers preaching violence and to investigate hate crimes. One of the first things Joe Ford did as the new head of the FBI in San Francisco was introduce himself to Muslim civic and religious leaders.
"We will vigorously investigate and protect the Muslim community from those who are ignorant of the inherent goodness of the vast majority of our citizens of the Muslim faith," said Ego (pronounced Egg-o). "Our unequivocal position is that the U.S. Muslim communities are really viewed as a very, very important element in the solution to preventing acts of terrorism."
Relationships between the FBI and mosques are "sprouting everywhere," said Safaa Ibrahim, executive director of the Council on American Islamic Relations' Northern California chapter.
"We as Americans want to ensure we're assisting the FBI in doing their job," she said.
As a result, the likelihood that signs of an attack plot would be reported to the FBI is "extremely great," she said. "People don't understand that the faith teaches us against the harm of innocent civilians, and that these types of acts don't discriminate they kill Muslims and Arabs as well."
The State Terror Threat Assessment Center in Sacramento and four regional centers one on the Peninsula funnel information about terrorist groups and their tradecraft down to local law-enforcement, as well as steering investigative tips to the FBI's task forces.
Alameda and Contra Costa counties also have their own Terrorism Early Warning Group that gathers intelligence and evaluates threats against local targets. Officers then draw up response plans. Two more such outfits are planned for San Jose and San Francisco. Los Angeles has a massive, $5 million joint intelligence center, a kind of one-stop shop for terror intelligence and investigations.
Meanwhile, at the urging of the state Office of Homeland Security, half of California's 400,000 licensed, private security guards have gotten four hours of training in spotting and reporting signs of terrorist planning. The rest will be trained as their licenses are renewed.
If they see someone conducting surveillance on a chemical refinery or photographing odd things such as an electrical box, their report is added to a database of "preincident indicators." State intelligence officers look for spikes in unusual or suspicious activity and can recommend more security.
Aside from one joint terrorism task force, none of those organizations or arrangements existed in 2001.
"Inside the United States, we're definitely better," said Chris Hamilton, former chief of Palestinian militant investigations for the FBI. But will the new cooperation reliably detect planning for attacks in time to stop them? "Nobody knows for sure," he said.
One problem is Washington itself. Agencies still fight for turf and money, and there is no consensus on who leads the war on terror the Department of Defense, the Director of National Intelligence or the Department of Homeland Security?
Meanwhile, terrorist threats have multiplied. New groups are emerging and, according to counterterror experts, finding a larger recruiting pool than existed in 2001, one swelled by images of dead civilians in the Muslim world.
Al-Qaida no longer exists as the corporate-style terrorist group that it was in 2001 its leadership has been forced into hiding by the invasion of Afghanistan and degraded by the killing or capture of key al-Qaida players. Instead, al-Qaida has fractured into cells that can mount attacks without central control.
"Al-Qaida has evolved more into a mindset or ideology, and I think there are people or groups out there inspired by it," said Ego.
Counterterror authorities worry that global flashpoints involving U.S. interests and allies Iraq, Lebanon, Israel and Palestine, the Kashmir region are serving as a rallying cry for violent extremists abroad and in the United States.
"The invasion of Iraq has done us no good at all," said Hamilton. "It's created a terrorist training camp. My opinion is the only way to defeat a terrorist organization is to get people to not join. In Iraq, they're lined up at the door to participate."
Proficient attackers also could come from the ranks of Hezbollah, Hamas, Palestinian Islamic Jihad, factions of the Iraq insurgency and self-recruited individuals inside the United States.
"Those kinds of things do contribute toward homegrown terrorism," said Ego of the FBI's San Francisco office. "That's our concern, that we're not only subject to foreign jihadists, but ones here at home."
California has been prime fund-raising territory for Hezbollah, especially in the Central Valley and Los Angeles, where police have discovered Hezbollah supporters selling knockoff Gucci handbags, Louis Vuitton watches, Prada shoes, DVDs and bootleg tobacco.
As Israel dropped U.S.-supplied bombs on Lebanon, the FBI quietly asked its field agents to look for signs that Hezbollah or other Iranian proxy terror groups are preparing for action inside the United States.
In his book "Hamas: Politics, Charity, and Terror in Service of Jihad," former FBI counterterrorism analyst Matthew Levitt reported that a 2002 bureau analysis found "50 to 100 Hamas and Hezbollah operatives had infiltrated the United States." Fund-raising may be their business for now, but experts say past experience suggest all have military training and could perform attacks if called upon.
Every counterterror expert interviewed said that the United States eventually will have more terror attacks inside the country.
"In this homeland-security business, we need to bat 1,000 percent. We just all know that's not going to be achievable in the long run, and we're engaged in a war against extremism that is in it for the long run," said Bettenhausen of the governor's Homeland Security Office.
With an open society and hundreds of critical targets in California alone, he said, "there is some inevitability."
Hurricane Katrina made most cities and states realize they weren't ready for a massive attack or natural disaster. Florida learned its lessons from Hurricane Andrew in 1992, and California from its "decade of disaster" through the mid-90s. But the latest scorecard from the Homeland Security Department suggests most of the nation is not prepared for the chaos following an attack or natural disaster.
"I don't care what anyone says, we didn't fix the problem in the 1990s," said George Foresman, homeland-security undersecretary for preparedness. "We may have put lipstick on the pig, but we didn't fix the problem."
More than $18 billion has girded hundreds of thousands of police, firefighters and medical personnel for lessening the toll in lives and property damage. Yet huge gaps remain, mostly the same vulnerabilities as five years ago.
Most cities and states still lack adequate communications. The Bush administration has hesitated to push industry into making radios talk to one another and been slow to open more airwaves for emergency communications.
But the biggest obstacle has been infighting among local agencies over who controls new regional radio networks and what language is used 10 codes or standard English.
Many cities and states also fall short on providing mass emergency medical care to victims of any large disaster. The latest federal data suggest big cities do better handling corpses.
Most cities and states have inadequate plans for mass evacuations and shelter of evacuees. They can handle evacuation of one or two square miles, said DHS' Foresman, but not evacuation and shelter of more than 100,000 people, much less entire cities.
Many lack adequate coordination among local, state and federal agencies, and many don't know what kinds of equipment, food and human resources they have on hand or nearby to use in a disaster.
States have spent roughly 80 percent of their homeland-security dollars on gear, much of it inclined exotically toward dealing with the aftermath of a chemical, biological, nuclear or radiological attack. Yet the after-action reports on Hurricane Katrina show 46 percent of the shortfalls in response there were human poor coordination, lack of training and exercising, lack of preparation.
"I would very clearly say we are not where we need to be," Foresman said. "We want to see less emphasis on (buying) stuff and more on planning and exercising and capability."
Katrina dramatized the political downside of failing to coordinate, failing to move people especially the poor, ailing and elderly out of harm's way and failing to supply them with shelter, food and water.
"Hurricane Katrina reminded every state and local official that the eyes of America were going to be on them for the next natural disaster," Foresman said. "You don't want to be the one now to say, 'We weren't prepared after Katrina.'"