WASHINGTON — Three weeks after the Boston Marathon bombings, the US Department of Homeland Security is seeking to use lessons from the attacks to enhance community policing and more effectively prepare religious and civic leaders to spot the warning signs of homegrown terrorism, according to top officials.
The approach, while raising its own set of civil liberties concerns, is seen by officials as a potentially more effective and less intrusive way of combating terror than expansive electronic and photographic surveillance powers or massive security sweeps at public events.
"How do we take the knowledge that we have acquired looking at these events and incorporate that into our community-policing efforts so that communities are better able to recognize an emerging threat, irrespective of the motivation, [and] prevent the threat from materializing?" explained John Cohen, the principal deputy counterterrorism coordinator at the Department of Homeland Security.
The approach requires a deep analysis of the Boston Marathon bombings by officials in a Department of Homeland Security program called Countering Violent Extremists, which was established in 2011 to devise new ways to confront homegrown threats.
Officials are profiling the psychology of the two Boston suspects, the tactics employed in the attack, and the interaction between law enforcement and local leaders to determine how additional outreach in the local community around Cambridge, where the two suspects lived, might have headed off tragedy, several officials said.
The goal of the review is to answer a key question: With additional training and encouragement, could local religious, education, or civic leaders have picked up on the emerging threat and alerted authorities?
The administration's desire for greater community engagement — which President Obama briefly mentioned in a press conference last week — is emerging as some members of Congress and security specialists assert that the Boston bombings underscore the need for more aggressive forms of policing: more domestic surveillance, greater security at large public gatherings, and greater police powers than were granted after 9/11.
There have also been calls for more surveillance cameras in public places, and even spy drones to help prevent domestic terrorist attacks or track potential suspects in the aftermath. Meanwhile, because the two primary Boston suspects were immigrants, others have advocated for a major tightening of border security.
But according to several top Obama administration officials, counterterrorism officials in Washington are taking a cautious approach to the calls for more layers of security, out of fear of overreacting and eroding Americans' civil liberties — a sacrifice that still may not make the nation safer.
"What are we willing to give up in terms of our freedoms to achieve security we're probably never fully going to get anyway?" said a senior Homeland Security official, who was not authorized to speak publicly.
But some local leaders also are wary about "community engagement'' aimed at early detection of certain behavior, concerned that it could lead to a system of domestic informants and unwarranted scrutiny of innocent people.
"I would be very nervous about perpetuating a culture when we are giving people a list of things that are indicators someone might be a threat to our national security, when there really is no profile," said Ayanna Pressley, councilor-at-large on the Boston City Council.
Pressley, who was in Washington on Friday for a panel discussion on the lessons of the Boston attacks sponsored by the Truman National Security Project, agreed communities "should have a heightened and greater awareness of anyone who appears to be distressed."
"But we need to tread very lightly here," she added.
Civil liberties groups have also long been concerned about empowering local law enforcement or others to monitor individuals or organizations for possible criminal or terrorist behavior. Last fall, the Massachusetts ACLU obtained, through a suit against the Boston Police Department, intelligence reports that designated peace activists as "extremists."
Meanwhile, so-called law enforcement "fusion" centers, designed to disseminate information on possible terrorist activity, have come under fire from Congress for unjustified invasions of privacy.
In the wake of the Boston attacks, the ACLU's national office urged Americans to resist the urge to profile people with particular backgrounds.
"Our nation needs to stay the course and judge people by their actions and their character, rather than the color of their skin or their religion or beliefs," the organization said in a statement. "This is what makes America great."
Cohen, a Lexington native who previously served as homeland security adviser for Governor Mitt Romney, said separate government reviews will determine if early warnings from Russia about suspect Tamerlan Tsarnaev, whose name was added to a pair of terror watchlists in 2011, should have triggered more action or scrutiny from authorities.
The FBI investigated in 2011 whether Tsarnaev was becoming increasingly radicalized and determined he did not pose a threat.
In the meantime, Homeland Security is using the Boston attacks as a case study to develop better profiles of potentially violent individuals.
"We have developed an analytic process where we look at the event, we look at the tactics used in the event, we look at how the event was prepared for by the perpetrator, we look at the behaviors and indicators that were exhibited," Cohen said. "We work with experts in the field — behavioral profilers and others — to get better understanding of the psychological dynamics of the individual or groups of individuals who carried out the attack."
Government studies of previous large-scale attacks perpetrated by religious extremists, antigovernment groups, and the mentally disturbed have highlighted certain shared patterns, officials say.
"When you take motivation out of it," said one US official involved in reviewing the homeland security implications of the Boston attack, "the indicators that are apparent to people are in many cases common across the board.
"In all of these cases there are opportunities for intervention. It may not be law enforcement at all times that is best suited to do it. It may be a teacher. It may be a faith leader," the official said.
President Obama, speaking at a White House press conference on Wednesday, cited the benefit of enlisting well-informed community leaders in schools, churches, and other civic institutions to be part of an early warning network.
"Are there more things that we can do, whether it's engaging with communities where there's a potential for self-radicalization of this sort?" Obama proposed. "Is there work that can be done in terms of detection? But all of this has to be done in the context of our laws, due process."
Such efforts, including training police cadets and organizing seminars for religious and other community leaders, have been expanded in the past two years under a plan Obama approved in 2011 called the "Empowering Local Partners to Prevent Violent Extremism in the United States.''
"Our best defenses against this threat are well-informed and equipped families, local communities, and institutions," the plan stated. "Law enforcement plays an essential role in keeping us safe, but so too does engagement and partnership with communities."
Bryan Bender can be reached at email@example.com. Follow him on Twitter @GlobeBender.