By Joby Warrick and Spencer S. Hsu
Monday, May 3, 2010; A01
The would-be bomber who left his smoldering SUV in the heart of Midtown Manhattan used the simplest of ingredients: gasoline cans, propane tanks, the kind of ordinary black powder found in cheap roadside fireworks.
But it was the simple nature of those components that made the attempted bombing relatively easy to execute and nearly impossible to detect, according to U.S. officials and terrorism experts. In that way, they said, it was similar to a series of other failed terrorist plots in recent months.
Both the Times Square bombmaker and the man who pleaded guilty in the plot to bomb the New York subway system last fall used recipes that required nothing more challenging than Internet research and a trip to the hardware store or beauty supply shop. While both attempts failed, the same kinds of simple ingredients have been linked to deadly attacks in the past, former and current intelligence and law enforcement officials said.
" 'Unsophisticated' can still cause a lot of pain and misery," said a U.S. counterterrorism official who spoke on the condition of anonymity because of the sensitive nature of the investigation.
The official described the latest bungled bombing as a reminder of how even a crudely constructed attack on an iconic American landmark can slip past the unprecedented security measures implemented after Sept. 11, 2001.
"These events are so hard to detect in advance," the official said. "If there were a foolproof way of finding people before they acted, whether it's the [snipers] in D.C. or someone who puts a bomb in his car . . . it has to be understood how very difficult this business is."
For years, homeland security and FBI officials have warned about the use of propane tanks, gas cylinders or other devices in vehicles. Such warnings were based largely on intelligence gathered in Iraq, where insurgents began deploying propane tanks in car bombs widely in 2007, and on a 39-page al-Qaeda bombmaking memo recovered in 2004 that advocated the use of materials from hardware stores or pharmacies.
Long before the Iraq war, Timothy J. McVeigh blew up a federal building in Oklahoma City in 1995 using a truck bomb consisting of 4,000 pounds of fuel oil and fertilizer.
Because bombmaking techniques require some time to master, the recommended recipes have frequently fizzled, but just as often they have been adopted by copycats and wannabes.
Two propane-based suitcase bombs were recovered from a failed attack aboard a German train in 2006 that was attributed to a domestic group. Three car bombs using propane and gas tanks packed with nails failed to detonate in back-to-back attacks on London and Glasgow, Scotland, in June 2007 that were carried out by a British-born Muslim doctor radicalized over the war in Iraq.
Attacks on the London public transit system in July 2005 relied on backpack bombs assembled from compounds found in nail-polish remover and hair bleach. Similar compounds were developed by Najibullah Zazi, the Denver airport shuttle driver trained by al-Qaeda who recently pleaded guilty to plotting to bomb New York's subway system last September.
Zazi received training in bombmaking in Pakistan, and terrorism experts cautioned against underestimating the capacity of lone-wolf operators to do significant damage.
"Often officials use the word 'amateurish,' when in fact the attempts turn out to be more complex than first portrayed," said Bruce Hoffman, a counterterrorism expert at Georgetown University. "Even if the bomb was amateurish, look at the target. New York has an image of being tough on terrorists, but that wasn't enough to prevent someone from putting a car bomb in the city's nerve center on a busy night."
It remained unclear late Sunday whether the Times Square bomber had ties -- ideological, practical or otherwise -- to al-Qaeda or other radical Islamic groups. While U.S. officials repeatedly cautioned against presuming links to Muslim extremists, the failed attack came against a surge of al-Qaeda-inspired plots on U.S. soil.
"From Fort Hood to the New York subway plot, terror at home increasingly has a radicalized American face," said Bruce Riedel, a former top counterterrorism official in the CIA. "We need to avoid a panic-driven Islamophobic response, but we do need to analyze closely these cases for insights into the radicalization process."
Frances Fragos Townsend, a top counterterrorism adviser in the George W. Bush administration, said a successful campaign against al-Qaeda in Pakistan has degraded the group's capability to launch another Sept. 11-style attack, the "spectacular, big attack with multiple, simultaneous events."
"But what that means is now you worry about the 'underwear bomber,' and the Zazi case with backpack bombs on subway trains," she said. Preventing such attacks is a harder challenge, one that requires well-trained local police officers and a vigilant citizenry, Townsend said. "Those are the people on the front lines when it comes to the individual one-off type of attacks," she said.
Staff writer Greg Miller and staff researcher Julie Tate contributed to this report.