Jacquelyn Martin, Associated Press
Vice President Joe Biden speaks during the White House Summit on Countering Violent Extremism, Tuesday, Feb. 17, 2015, in the Eisenhower Executive Office Building on the White House Complex in Washington. Biden opened a three-day White House summit aimed at countering the spread of violent extremism across the globe. He says solutions must go beyond military force and that "inclusion counts."

WASHINGTON — The United States must ensure that immigrants are fully included in the fabric of American society to prevent violent ideologies from taking root at home, Vice President Joe Biden said Tuesday as he opened a White House summit on countering extremism and radicalization.

Joining local elected officials, community leaders and religious figures, Biden portrayed the U.S. as far better positioned than Europe, thanks to what he called America's successful record at cultural integration.

Across the Atlantic, deadly terrorist attacks in Paris, Brussels and Denmark have left Europeans feeling vulnerable to the type of violent ideology promoted by the Islamic State group and once thought to be limited mostly to the Middle East and North Africa.

"National security flows from a sense of community," Biden said, adding that the most important lesson the U.S. can learn is that "inclusion counts."

Biden's comments came at the start of a three-day conference highlighting domestic and international efforts to prevent extremists and their supporters from radicalizing, recruiting and inspiring others, particularly disaffected young people. The conference is designed to share best practices and emerging strategies to prevent extremists from carrying out violent acts.

"When I say we have to be able to see one another, I'm not talking about surveillance, I'm not talking about cameras," Biden said, calling for U.S. cities to treat immigrant communities with respect. "Technology cannot replace contact."