NEW YORK - One year after a militant from Connecticut spread panic by driving a bomb-laden SUV into the heart of Times Square, New Yorkers, tourists and even the street vendor who alerted police to the smoking vehicle still descend on "The Crossroads of the World" as if it never happened.

But behind the scenes, the New York Police Department and other law enforcement agencies still watch for and worry about the next terror plot against the city, something they say is certain to come. Experts say that while al-Qaida remains a threat, the admitted would-be bomber in the Times Square case represented a modern breed of homegrown terrorist - one with perhaps less formal training and fewer resources than the Sept. 11 attackers, but with equal audacity and a willingness to stage smaller strikes that still have the power to paralyze a city.

"The old al-Qaida that we were familiar with after 9/11 was very centrally controlled," said Randall Larsen, head of the nonprofit Institute for Homeland Security. "Part of the new al-Qaida is providing training and motivation, and in some cases some money and equipment, to these splinter groups that are around the world."

Since the May 1 bombing attempt by Faisal Shahzad of Bridgeport, Conn., a naturalized U.S. citizen originally from Pakistani, the NYPD has continued to fine-tune trip wires it hopes will stop other would-be terrorists. Police have expanded programs to monitor the stockpiles and sales of fertilizer, household chemicals and other potential homemade bomb ingredients; to patrol the subways with bomb-sniffing dogs and heavy arms; and to use license-plate readers, closed-circuit cameras and radiation detectors to harden Wall Street and midtown targets against dirty bomb and other attacks.

The next attacker is more likely to be a less-sophisticated, "self-radicalized" terrorist, like Shahzad, who sees himself more a follower of an extremist social movement rather than a sworn member of a terror network, said Peter Romaniuk, a professor at John Jay College of Criminal Justice who specializes in international security and counterterrorism.

The Shahzad case "is part of the evolution of the terror threat," Romaniuk said. As for Sept. 11, he added, "that expeditionary-style of terrorism is less likely to occur these days."

A recently unsealed indictment in federal court in Manhattan is a reminder of how - compared with Shahzad - the Sept. 11 attacks were an elaborate undertaking that began as early as 1999 with admitted mastermind Khalid Sheikh Mohammed training the hijackers "to use short-bladed knives by killing sheep and camels."

Mohammed had tens of thousands of dollars wired to the sleeper cell in the United States in the months leading up to the attacks, the indictment said. He stayed in steady contact with the hijackers, instructing them in May 2001 "to take cross-country flights to study in-flight security measures" and "to meet in Las Vegas to make final preparations."

In late August 2001, he "was advised of the date that the hijacking attacks would be carried out and Mohammed notified Osama bin Laden of it," the document added.

By contrast, the Pakistan Taliban provided Shahzad with about $15,000 and only five days of explosives training in late 2009 and early 2010, months after he became a U.S. citizen.

On May 1, he drove a 1993 Nissan Pathfinder carrying his crude bomb into a busy section of Times Square, parked it and walked away. Street vendor Duane Jackson spotted smoke coming from the SUV and alerted police, who quickly cleared the area.

The discovery spread a wave of fear across the city and shut down Times Square for 10 hours as the bomb squad took charge. It discovered that the bomb - made of fireworks fertilizer, propane tanks and gasoline canisters - had, fortunately, misfired.

Part of the problem, explosives experts later said, was that the fertilizer wasn't the right grade and the fireworks weren't powerful enough to set off the intended chain reaction. A test showed that if wired correctly, it would have created a fireball capable of shredding cars and killing pedestrians in hundreds of feet in all directions.

The bomb attempt set off an intense investigation that culminated two days later with investigators plucking Shahzad off a Dubai-bound plane at Kennedy Airport.

Authorities say that once caught, Shahzad embraced his role and was eager to describe his failed plot. At sentencing, he warned Americans: "Brace yourselves, because the war with Muslims has just begun."

The anniversary is a reminder that New York "was lucky," said Police Commissioner Raymond Kelly. "We had an individual who was able to drive in there with what he thought was a functional bomb. It could have been a major catastrophe."

The attempted attack, Kelly added, was further proof "that there are people out there who are committed to coming here and killing us, and that we have to be vigilant."