'This Week' Transcript: Attorney General Eric Holder

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ANNOUNCER: A special edition of ABC's This Week: terror in Paris. A country on edge after a week of terror. Security in major cities around the world stepped up. The U.S. on alert. One of the highest threat levels since 9/11. Are other sleeper cells waiting to strike? How did terrorists with ties to al Qaeda slipped through the cracks?

This morning, breaking details, insight and analysis from our team around the world.

Plus, Attorney General Eric Holder and the Senate intel committee chair are here.

As hundreds of thousands gather this morning in Paris refusing to be afraid.

From the global resources of ABC News, a special edition of This Week: Terror in Paris.

Here now, chief anchor George Stephanopoulos.

GEORGE STEPHANOPOULOS, HOST: And you are looking at the scene in Paris. Right now, marchers in the streets, up to a million, joined by political leaders from all over the world all gathering in solidarity against the worst attack by radical Islam that Paris has seen. Unprecedented security in place, the French prime minister now says his nation is at war.

And ABC's senior foreign correspondent Terry Moran is on the scene. Good morning, Terry.

TERRY MORAN, ABC NEWS CORRESPONDENT: Good morning, George.

It is an incredible moment here as this huge throng is just about to step off on this march of national unity, of solidarity and shared grief. Dozens of world leaders are going to be joining them later this evening. Security, as you say, is very tight.

The main feeling that you get in this crowd that was one of determination, as if the whole nation is rising up after being knocked down by the terrorist rampage this weekend declaring as one, no, we will not live in fear.

(BEGIN VIDEOTAPE)

MORAN: With Paris still traumatized by terror, security is very tight. Thousands of troops and police, plain-clothed officers in the crowd; roads and streets blocked off.

There's acute concern about copy cat attacks. And overnight in Hamburg, Germany the offices of a newspaper that published some of Charlie Hebdo's cartoons firebombed.

But in the bright winter sunshine, this day really belongs to them, streaming into the streets, young and old, in silence and raising their voices.

Across Paris, you can see the shock and national grief in this spontaneous memorials at the offices of Charlie Hebdo, in prayer services at churches and everywhere Je suis Charlie, "I am Charlie."

But for France's 5 million Muslims, many marching here, too, there is a different emotion: fear of a backlash. Mosques have been attacked.

We spoke with Attaf Abdel Baqi (ph), a leader of the mosque frequented by one of the Kouachi brothers.

"I won't hide from you or fear for our religious cites," he says. "The president has tried to calm things down, but because our religion is physically manifest in how we dress, yes, there's a fear."

To face down fear for colleagues and loved ones left behind, it is their moment, too.

Chloe Virloc (ph), widow of the famous cartoonist Tignous who now must raise their four children, the youngest 5-years-old, alone, she told us.

"We have a duty. We owe it to them to stand up. Because I have lost the love of my life who is the father of my children. But the country has lost an amazing cartoonist. He didn't belong to us, he belongs to the people."

(END VIDEOTAPE)

MORAN: So much emotion in the aftermath of these attacks.