The United States has made great strides in top­pling major orga­ni­za­tions that pose a threat to national secu­rity, said Stephen E. Flynn, the founding co-​​director of Northeastern’s George J. Kostas Research Insti­tute for Home­land Secu­rity. He deliv­ered his tes­ti­mony on Wednesday to the Senate’s Com­mittee on Home­land Secu­rity and Gov­ern­ment Affairs.

But he struck a note of cau­tion: The nation, he said, now more than a decade removed from 9/​11, con­tinues to remain at risk from small-​​scale attacks from home­grown ter­ror­ists and those loosely affil­i­ated with al Qaeda.

“Major attacks require a group of oper­a­tives directed by a leader, com­mu­ni­ca­tions with those over­seeing the plan­ning and time to con­duct sur­veil­lance and rehearse the attack. … All this effort ends up cre­ating mul­tiple oppor­tu­ni­ties for detec­tion and inter­cep­tion by intel­li­gence and law enforce­ment offi­cials,” Flynn tes­ti­fied. “Alter­na­tively, small attacks car­ried out by one to three oper­a­tives, par­tic­u­larly if they reside in the United States, can be car­ried out with little plan­ning on rel­a­tively short notice.”

He added: “As such, they are unlikely to attract the atten­tion of the national intel­li­gence com­mu­nity and the attacks, once underway, are almost impos­sible for the fed­eral law enforce­ment com­mu­nity to stop.”

Wednesday’s hearing, which was con­vened by the committee’s chairman, Con­necticut Sen­ator Joseph Lieberman, aligned with Northeastern’s focus on use-​​inspired research that solves global chal­lenges in health, secu­rity and sustainability.

In the hearing, Flynn also dis­cussed the ongoing vul­ner­a­bility of trans­porta­tion sys­tems to mass dis­rup­tion and nat­ural dis­as­ters as “the clearest and most present home­land secu­rity danger.”

The United States, he noted, is more likely to face terror threats than tra­di­tional mil­i­tary engage­ments because of its unique posi­tion as a global superpower.

“Quite simply, it has become reck­less for our cur­rent and future adver­saries to chal­lenge the United States by engaging in the kind of war­fare we are best pre­pared to fight,” Flynn said. “Their better option is to take the battle to the civil and eco­nomic space as opposed to engaging in direct combat with our second-​​to-​​none armed forces.”

Flynn, speaking as part of a high-​​level panel that included four-​​star Air Force gen­eral Michael Hayden, stressed the impor­tant role uni­ver­si­ties play in responding the cyber­se­cu­rity threats and as an honest, non­par­tisan broker between gov­ern­ment and industry — the kind of work hap­pening now at the new Kostas Insti­tute. Chairman Lieberman expressed sup­port for this model during the hearing.

Sen­a­tors at the hearing — including Lieberman, ranking member Susan M. Collins (R-​​Me.), and Sen­a­tors Scott Brown (R-​​Mass.) and John McCain (R-​​Az.) — engaged in sub­stan­tive con­ver­sa­tion over the future of national secu­rity leg­is­la­tion, with McCain expressing serious con­cerns over the prospect of passing cyber­se­cu­rity leg­is­la­tion, just one of many national secu­rity topics dis­cussed in depth.

In closing, Flynn noted that the nation’s best defense against a small-​​scale terror attack is a sense of national resilience, adding that ter­ror­ists rely on knowing that even a small attack will res­onate on a national level.

“How we respond to acts of ter­rorism effects our adver­saries’ cal­cu­la­tions in under­taking these attacks,” Flynn said. “If we pro­vide them with a ‘big bang’ for their rel­a­tively modest buck, we end up fueling the incen­tive for ter­rorist activity.”

Flynn’s tes­ti­mony before the Senate com­mittee fol­lowed a Tuesday meeting of the Depart­ment of Home­land Security’s Aca­d­emic Advi­sory Com­mittee, which was attended by North­eastern Pres­i­dent Joseph E. Aoun, a com­mittee member.

As the chair of the advi­sory council’s Sub­com­mittee on Aca­d­emic Research and Fac­ulty Exchange, Aoun lead a dis­cus­sion con­cerning the ways in which uni­ver­si­ties could address the needs of the Sci­ence and Tech­nology Direc­torate of DHS.

Tara O’Tool, under sec­re­tary of the Sci­ence and Tech­nology Direc­torate at DHS, noted that its lack of resources and diverse nature makes it dif­fi­cult to artic­u­late higher education’s role in addressing its grand challenges.

O’Tool praised the DHS Uni­ver­sity Cen­ters of Excel­lence, one of which North­eastern leads, but sug­gested that the rela­tion­ship between uni­ver­si­ties and the DHS should be reeval­u­ated. This led to a very infor­ma­tive dis­cus­sion among council mem­bers, but will require fur­ther delib­er­a­tion before addi­tional rec­om­men­da­tions can be sug­gested by the Sub­com­mittee to Sec­re­tary Janet Napoli­tano regarding ways in which the uni­ver­sity com­mu­nity can fur­ther engage with DHS.