According to the authorities, the target of the plot was not the Holland Tunnel, but rather two commuter rail tunnels running under the Hudson River that connect New York City and New Jersey. Officials at the press conference -- who included Mark Mershon, the special agent in charge of the FBI's New York field office, New York Police Commissioner Raymond Kelly and Samuel J. Plumeri, the director of the New York/New Jersey Port Authority Police Department -- said they had been aware of the plot for about a year.

At their request, authorities in Lebanon arrested a man at the center of their investigation -- 31-year-old Lebanese national Assem Hammoud -- in late April. (Hammoud also uses a nom de guerre, Ameer Andalusi, which was the name originally reported in the Daily News story.) At the press conference, authorities also emphasized that no imminent threat had been posed to the rail tunnels before Hammoud was arrested. As Police Commissioner Kelly put it: "There was a lot of discussion, there was planning being done; but there was no indication that there was any movement toward these facilities." He added, "There is no indication that materials were secured or that specific reconnaissance was done."

The New York tunnels case is interesting to study -- not because anything actually happened, but because of what it reveals about the current state of jihadism in the United States and, even more significantly, the approach the U.S. government is taking in ensuring that potential plots do not give rise to actual attacks in the homeland. As this case clearly demonstrates, the counterterrorism approach has shifted from one based on waiting until a strike is about to be carried out -- and then "making the big case" -- to one based on the concept of pre-emption and taking action at the earliest possible stage.

The New York Tunnels Case Like other suspects arrested in the United States and Canada, it appears that Hammoud, and the other men he allegedly was conspiring with, conform to what we refer to as the al Qaeda 4.0 model. That is, they appear to be part of a loose but cohesive network of grassroots jihadists who think beyond their immediate area and who have contact with jihadists elsewhere -- usually via the Internet. As we have noted previously, the Internet is both a great enabler and an Achilles' heel for such groups. That appears to have been the case with Hammoud, whose postings in a jihadist chat room brought him to the attention of authorities.

Given the similarities between some aspects of the cases, it would not be beyond the realm of possibility that Hammoud may have had connections to other suspects who have been arrested previously in Canada, Britain and the United States. The investigation into his online activities began last summer, before the suspects in the earlier cases had been arrested, and all were allegedly planning bombings of some type against targets easily within their reach. We have no information to support such speculation, but given the totality of the circumstances and considering the intelligence-sharing between local, federal and foreign law enforcement agencies, it is a plausible theory.

The fact that Hammoud and his counterparts reportedly were talking about bombing a commuter rail line in New York should not be surprising either. Even before the high-profile bombings in Madrid and London, it was apparent that passenger rail systems were highly vulnerable to terrorist attacks -- and the events this week in Mumbai have further underscored that the risk remains real.

A Legal Evolution Just as clearly, the case in New York illustrates the extent of the shift in the U.S. government's philosophy concerning the best ways to prosecute terrorism cases. The philosophy has changed drastically during the course of the past 15 years -- often as a result of painful experience.

Prior to the 1993 World Trade Center bombing, there were no "terrorism" statutes, such as the laws now on the books concerning the use of weapons of mass destruction or acts of terrorism transcending national borders. Instead, prosecutors in terrorism cases struggled to find existing laws they could apply. The defendants in the 1993 New York bomb plot trial -- in which Sheikh Omar Abdul-Rahman (the "Blind Sheikh") and some of his followers were accused of planning strikes against the Lincoln Tunnel and other New York City landmarks -- were not charged with conspiring to build bombs or commit acts of international terrorism. Rather, the charge on which they were convicted was "seditious conspiracy."

Similarly, it is not widely recognized that Mohammed Salameh, who was convicted for his role in the 1993 World Trade Center bombing, actually was charged violating the Special Agricultural Worker program and for damaging U.S. Secret Service cars stored in the basement of the Trade Center building.

In light of the challenges in prosecuting the 1993 New York cases, Congress eventually passed specific terrorism statutes in the mid-1990s. However, until the 9/11 attacks, the emphasis remained on prosecution rather than prevention. In other words, "making the big case" was a priority for law enforcement and prosecutors. That meant that agents and police officers assigned to the Joint Terrorism Task Forces investigating the cases and the assistant U.S. attorney(s) they coordinated with wanted to have all the goods on a suspect before proceeding to act on a terrorism case.

9/11 and Broken Windows

After 9/11, this paradigm changed again with the PATRIOT Act, which amended many statues in order to ease the prosecution of terrorist crimes. For example, the definition of "material support" in a statute on providing material support to terrorists (18 USC 2339A) was altered to include providing "expert advice or assistance" and "monetary instruments." This statute, by the way, has been invoked several times in the recent past -- including the recent case of the "Miami Seven" and a 2005 case involving an FBI sting operation.

Additionally, authorities have cracked down on people who raise money to support jihadist struggles in places like Kashmir and have aggressively used statutes on immigration fraud, financial fraud or tax evasion charges to go after potential terrorist threats. In fact, the combination of these newer statutes and the philosophical shift have allowed the government to pursue a terrorism policy that is similar to the concept behind the "zero tolerance" or "broken window" theory of policing. That is, there is a belief that if authorities come down hard on all "potential threats" before they become "imminent threats," terrorist attacks can be pre-empted and prevented, rather than merely prosecuted. As Homeland Security Secretary Michael Chertoff said in discussions of the New York tunnels case: "We did not wait, and we do not wait, until the fuse is lit; we swoop in as early as possible."

The policy also has been evident in government prosecutions of animal rights extremists and white supremacist groups. The fact that Shaun Walker, the chairman of the neo-Nazi National Alliance, was recently arrested on federal charges for a 1993 Salt Lake City bar fight is further proof of this concept; there have been untold thousands of bar fights, before and since Walker's, that were not prosecuted at the federal level.

Threats and Resource Management The "broken windows" policy -- a label that hearkens back to former New York Mayor Rudolph Giuliani's zero-tolerance approach to vandalism and street crime -- is not without controversy. In several cases -- for example, the arrests of the "Lodi cell," the "Lackawanna Six," the "Toledo Three" or the recent group in Miami -- there has been some outcry about authorities cracking down on people who do not appear to pose an imminent threat. It has been argued that the government looks foolish when it hypes the arrests of such suspects, that the publicity drawn to such cases is part of the internal competition between federal agencies for resources, that resources are being wasted on relatively harmless cases instead of deployed in the pursuit of "real terrorists," and even that the government is rounding up goofballs because its agents couldn't find more sinister, professional operatives.

There may be some merit to these arguments at times, though in our view there is ample evidence of small-time, untrained "terrorists" being able to cause very real and significant bloodshed and damage.

Viewed from another angle, though, the zero-tolerance "broken windows" policy appears to be a prudent use of scarce law enforcement resources. For example, the government could have chosen to monitor the suspects in the "Miami Seven" case for years -- waiting for an imminent threat to develop -- before stepping in to make arrests. For example, it might be recalled that Narseal Batiste and his associates in the Miami case were believed to be trying to make contact with al Qaeda for logistical support and training, but were subverted by an informant who contacted federal authorities. It would have been difficult for law enforcement to avoid following up on the tip; had it done so, the efforts to contact al Qaeda likely would have continued and perhaps eventually would have succeeded. But long-term surveillance and monitoring also chews up quantities of man-hours and resources. Moreover, there is always a chance that the cell in question could somehow burn or fool the informant and manage to carry out an attack, despite being under surveillance by authorities. (This is obviously an outcome that no government law enforcement official would want to have to explain to the next "9/11 Commission.")

Instead, in cases like the Miami Seven -- or this latest case in New York -- the government is choosing to investigate suspect cells for a few months, gather sufficient evidence to support the elements required for a prosecution, and then roll them up as soon as those criteria are met. With the suspects in the bag, they can redirect resources to investigate the next potential threat.

A "broken windows" approach is not a perfect answer to the problem of terrorism. The resources available to federal, metropolitan and other governments will always, by definition, be finite, and as such there is always the potential that they could be overwhelmed by organized groups that "ping the system" with false alerts, or diverted by sophisticated actors using disinformation campaigns. But those pitfalls assume the existence of committed, organized and sophisticated groups that are able to engage in such activities on a meaningful scale -- and it is not at all clear that al Qaeda or its "grassroots jihadists" currently fit the bill. Ultimately, the "broken windows" policy may be the most realistic of the options currently available. The potential downsides certainly do not outweigh the upsides -- and history attests to the dangers and failures of the "make the big case" approach.