"It's not 9/11," Steven MacMartin, a former senior special agent with the U.S. Department of Homeland Security, said, and "you're not going to see the kind of changes you saw after 9/11."
Based on the information that had been released on Friday, this appears to be what terrorism experts categorize as a 'lone wolf attack.' And for Homeland Security, those are "nightmare scenarios," because you can't see them coming, MacMartin, now the director of the homeland security program at Medaille College in Buffalo, N.Y., told CBC News.
Joseph Ryan, a former consultant to the Department of Homeland Security and a former New York police officer, told CBC News, "the information that's emerging about these two brothers doesn't tell us anything that's significant that we could have identified. It's the same thing in Aurora, Colorado and in Newtown, Connecticut."
Dzhokhar, 19, and Tamerlan Tsarnaev, 26, the brothers who police suspect were behind the Boston Marathon bombings, immigrated to the United States with their family about a decade ago.
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MacMartin said that the family's Chechen origins and whether or not they are U.S. citizens are "kind of irrelevant," because of length of time they had lived in the U.S. "These guys could have been Timothy McVeigh," he said, referring to the 1995 Oklahoma City bomber.
At a media briefing Friday evening, Massachusetts police spokesman David Procopio said that "The motive remains under investigation."
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Canadian terrorism expert Christian Leuprecht considers the brothers "home-grown."
The three experts are all aware of the speculation that the brothers could have foreign links but they stressed that they are not aware of any evidence.
However, Leuprecht, who's a professor of political science at both the Royal Military College of Canada and Queen's University in Kingston, Ont., said, "If they travelled abroad and picked up their violent ideas and training there, that would be a significant game-changer: security intelligence services' great concern is citizens or permanent residents travelling abroad, then importing violence (or diffusing violent ideas) upon their return."
No reason to improve border security
So far there doesn't appear to be any reason for the U.S. to improve its border security because of the Boston attack, the experts say. Ryan, who now chairs the criminal justice and security department at Pace University in New York, said it would have been almost impossible in this case for immigration officials to determine whether or not they were going to a threat to the country.
While the 9/11 Commission report did call for changes to the American immigration system, because of what they considered an information disconnect between the border entries and citizenship and immigration, MacMartin said that, "Although that hasn't cleared up totally, it is operating much better and the immigration system worked very well in this case."
In fact, MacMartin thinks that one reason police identified the brothers so quickly was in part because the immigration information was there.
No knee-jerk reaction
After an event like Boston, Leuprecht noted the risk of a knee-jerk reaction "to implement all sort of security measures that really in the end would have done nothing to actually prevent or decrease the chances of this type of attack but that's not what we're seeing."
Noting that the U.S. cannot have 100 per cent security all of the time, so something is going to slip through the cracks, Leuprecht told CBC News, "we just need to make sure, on the one hand, we have the legal and other deterrence mechanisms in place to make sure people don't actually act on these sorts of ideas [about politically motivated violence] and that when they do, that we have the security and intelligence and law enforcement mechanisms in place to demonstrate that people will not get away with this type of activity.
"The efficiency with which this operation appears to be running seems to demonstrate that," he added.
From his experience, MacMartin argued that if the Boston bombings "had happened in 2002, in 2003 or in 2004, the response would have been different each time." He said that over time the response to a security threat in the U.S. has improved. "The country is different now."
While MacMartin expects there will be changes in how security is handled at marathons, or any event in a wide-open space that cannot be cordoned off, both he and Ryan said the main change is that Americans will become more vigilant. "That is the new normal," Ryan explained.
"See something, say something" has long been a Homeland Security slogan, however, MacMartin said "public awareness has dulled a little bit" but now people will naturally "ramp up their watchfulness."
In the investigation that followed the attack, Ryan, now a police instructor, said that "to track down these two alleged suspects in such a short period of time is phenomenal."
The investigation also has impressed MacMartin, who noted, "You learn something every time and no matter how well you want to judge this response there will be things that they can learn and those things will be instituted in new plans."
Ryan, however, does wonder about the unprecedented action by authorities to shut down Boston, given the cost. "We're going to hear more about that in the next couple of days."
Looking ahead, Leuprecht said, "When an attack does happen the best way to deter future attacks is to show that society bounces back quickly, that society does not buy into the psychology of terrorism, of fear, of civic, economic, political paralysis."
"If we don't act in a resilient manner, then in a way the terrorists have won," he added, noting that the main goal of terrorism is to instill fear but "if we show that we're not scared and show we're not deterred, that's the best way to show that these attacks are relatively meaningless."
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