Homeland Chief Johnson: Lone Wolf Still a Threat

The government's homeland security secretary says the United States is safer now than it was in 2001 against what he calls "another 9/11-style attack."

But Jeh Johnson — making the rounds of the Sunday news shows — says the country is "challenged when it comes to the prospects of the lone-wolf actor, the homegrown violent extremists."

He told NBC's "Meet the Press" that requires "a new, whole of government response and public participation and vigilance."ional Memorial in Shanksville.

"We're on a constant state of alert, against not only the terrorist-directed attack of the 9/11 attack but also terrorism-inspired attacks, the so called lone wolf, the homegrown violent extremists," Johnson said on CNN's "State of the Union."

"We're in a relatively new environment now where we've got to be concerned about the traditional threat as well as this new threat."

Johnson said the country is safer today than it was 15 years ago when it comes to the "9/11-style attack."

"We're better now with detecting the 9/11 style attack, but it's more challenging now with this new environment we're in," Johnson said.

"There's this phenomenon now of the terrorist-inspired attack, the lone wolf -- that's the thing that presents the challenge most directly for our homeland," he continued.

"It's frankly the thing that keeps me up at night."