Updated

This is a rush transcript from "Special Report," April 15, 2013. This copy may not be in its final form and may be updated.

(BEGIN VIDEO CLIP)

UNIDENTIFIED MALE: Where did you see the first bomb go off again?

UNIDENTIFIED MALE: On the right-hand side of Boylston, just past the blue paint up there. You could see the white smoke come out. And then it was about 15 seconds later also further up on the right-hand side, the second explosion.

UNIDENTIFIED MALE: Basically a huge plume of gray smoke goes straight up and then that was much louder explosion. And then just shortly thereafter, there was another secondary explosion, but it was not as loud. And of course, then we sat there and asked the people, well, did they shoot cannons off or something like that, because we didn't know. And they said no. So then we just kept asking what was going on.

(END VIDEO CLIP)

BAIER: Let's bring in our panel tonight. Steve Hayes, senior writer for The Weekly Standard, Juan Williams, columnist with The Hill, and syndicated columnist Charles Krauthammer. Charles, your thoughts, Charles?

CHARLES KRAUTHAMMER, SYNDICATED COLUMNIST: What strikes me is part of the reason for the psychological shock is that if you think about it, Bret, this is the first successful bombing, terror explosion, since 9/11. We've had some that were attempted, like the one in Times Square that never succeeded. We've had, by my count, about 10 terror attacks in the U.S. since 9/11, all of them have been shootings, with one exception, which is a man who drove a car into a crowd at University of North Carolina. But this is the first explosion. I think that's what gives this the sort of psychological resonance, people running in the street of a big city, the smoke.

Of course, it's nowhere near the scale of 9/11, but it's the first time. And I think that is sort of the historical echo that we're feeling, and it reminds us of how vulnerable we felt at the beginning of this whole decade of terror. And that even though we thought we had largely escaped -- and we have largely escaped -- it is still out there.

BAIER: Juan?

JUAN WILLIAMS, SENIOR EDITOR, THE HILL: Heritage reports we've had 50 plots that can be called terror plots since 9/11. And you think back here, the key issue is, is it a domestic plot or is it a foreign plot? Here in D.C. we have had some plots that were done by foreign nationals or at least people who were foreign born. I'm thinking recently of an attempt to assassinate the Saudi ambassador. In fact, I guess it was just about last year that a Moroccan was charged in a plot to try to blow up the U.S. Capitol.

But then you think back to things like the Manhattan synagogue; a bomb plot against George W. Bush and other officials down in Texas by a Saudi – a Saudi student. And then, of course, you think of what Charles just mentioned, what happened in Times Square. But then you go overseas and you start to look at Benghazi, you look at what happened on London subway. You look at what happened in Madrid. You look at what's happened in Southeast Asia and some of the resorts. And you understand this problem is never going away. It is the case that we in the United States, since 9/11, have been so blessed not to have this as a constant part of our lives. We have hardened targets from malls to subways to movie theaters and schools. We have things that you could call domestic terrorism. The question in my mind is always is this, because of our 9/11 experience, somehow linked to the Al Qaeda type of action. People who are against us because we are Americans, because of our beliefs and what we stand for as a global leader.

BAIER: Steve Hayes?

STEVE HAYES, SENIOR WRITER, THE WEEKLY STANDARD: Well, this certainly has all the hallmarks of a terrorist attack. I mean, we have multiple bombs, different sites. You have ball bearings or some kind of projectiles included in them. It was obviously designed for maximum exposure there were television cameras. Lots of media there at the site that this took place. So I think it's pretty clear at this point that it was terrorism.

But I would echo what Brit Hume earlier. I would give the president a wide berth here. He was speaking just three hours after this attack. I think it was fine that he didn't use the word "terrorism." I understand why people are asking that question of the president and the administration. There have been times in the past when we have known quite a bit more than we know about this particular attack both after the Christmas Day bombing and after the Times Square bombing where the administration certainly seemed to down play the prospect of terrorism.  But, in this case, the president, as I mentioned, was speaking just some three hours after the attack. And while we know that this has all the hallmarks of a terrorist attack, I think is he fine.

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