(AP)  WASHINGTON — State and local law enforcement officials convened at the White House on Wednesday for a daylong discussion about how police can maintain the trust of their communities while identifying and preventing violent extremism and homegrown terrorism — an effort the administration considers critical to national security.

It’s a delicate balance, as the violent extremism that has erupted across the U.S. in the past few years has been motivated by an ideology, whether a violent interpretation of Islam or white supremacist beliefs. Ideologies in and of themselves are not illegal. But police now find themselves struggling with identifying the ideologues who plan to commit violence among the many others who hold similar beliefs but have no intention of hurting anyone.

“Where do you draw the line between what they say and what they do,” Cambridge, Mass., Police Commissioner Robert Haas said in an interview during a break. Police can’t be seen as violating the trust they’ve built in local communities to ferret out information that potentially could prevent an attack, he said. Haas was one of the 46 senior federal, state and local law enforcement officials who participated in the event that was closed to the public.

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