GWEN IFILL: The latest on the Boston bombings; the new Syrian threat; the shaky Senate; and George W. Bush's legacy, tonight, on "Washington Week."

VICE PRESIDENT JOE BIDEN: (From tape.) Whether it's al-Qaida Central out of the FATA or two twisted, perverted, cowardly knockoff jihadis here in Boston, why do they do what they do?

MS. IFILL: Nearly two weeks later, still sorting through the whys and the hows behind the Boston terror attack while new worries spring up abroad, this time in Syria.

DEFENSE SECRETARY CHUCK HAGEL: (From tape.) The Syrian regime has used chemical weapons on a small scale in Syria, specifically the chemical agent Sarin.

SENATOR JOHN MCCAIN (R-AZ): (From tape.) I think it's pretty obvious that red line has been crossed.

MS. IFILL: Yet another Democrat abandons the Senate while other Democrats are getting nervous. And in Texas --

MAN: (From tape.) President George W. Bush.

The presidents' club gathers to open its newest library.

FORMER PRESIDENT GEORGE W. BUSH: (From tape.) The political winds blow left and right, polls rise and fall, supporters come and go, but in the end leaders are defined by the convictions they hold.

MS. IFILL: Covering this remarkable week, Martha Raddatz of ABC News, James Kitfield of National Journal; Susan Davis of USA Today; and Dan Balz of the Washington Post.

ANNOUNCER: Award-winning reporting and analysis, covering history as it happens, live from our nation's capital this is "Washington Week with Gwen Ifill."

(Station announcements.)

ANNOUNCER: Once again, live from Washington, moderator Gwen Ifill.

MS. IFILL: Good evening. It's been a puzzling week with more questions than answers on crime, punishment, war and politics. We start with the investigation into the Boston bombings. Dzhokhar Tsarnaev is in prison tonight, held as the prime surviving suspect in last week's attacks. And lawmakers are debating how to stop it from happening again.

SENATOR LINDSEY GRAHAM (R-SC): (From tape.) We need to understand that bin Laden may be dead, but the war against radical Islam is very much alive. Radical Islam is on the march. And we need to up our game.

SECRETARY OF STATE JOHN KERRY: (From tape.) I think the world has had enough of people who have no belief system, no policy for jobs, no policy for education, no policy for rule of law, but who just want to kill people because they don't like what they see. There's not room for that.

MS. IFILL: But what to do? Revoke the suspects' citizenship? Refuse to extend the right to legal representation? Find a new way to distinguish between lone threats and al-Qaida threats? All those things and more appear to at least be on the table. So what of those things is up first?

Well, I think determining whether it's lone wolf or whether there was some distinct link to terrorism. I think that's -- or extremists abroad. I think that's what they're focusing on right now. I think, initially, they think, yes, they're lone wolfs; there's no threat right now in Boston, but is there a link in their homeland?

Was or were -- was the older brother up to something when he visited Russia? I mean, my reporting is that he met with extremists at some point there. And that's what they really do want to dive into now to see if this is bigger, to see if there are lots more lone wolves out there, to see if they all come together and spread out and do different things.

MS. IFILL: Let's just talk about these two brothers, the Tsarnaev brothers, James. Are they -- what do we know about their relationship and the degree to which this plot is something that had been hatched over a period of time?

Well, apparently, if you believe the interrogation of the younger brother, who's in our custody, badly wounded, it was only in the last couple of weeks when he came -- he was sort of radicalized by his older brother, who was really the -- you know, the brains behind this plot.

I agree with Martha that six months in Russia, he comes back, and suddenly starts posting jihadi videos on a YouTube website indicates something happened in that time. Now, whether it was connected to an organized terrorist group or not, we don't know yet.

I will say what's interesting to me is that he was pinged by our counterterrorism, you know, forces. He was interviewed by the FBI at the behest of Russia. He got on our -- along with mother, got --

MS. RADDATZ: Which started in 2011, when the Russians were concerned, even before he started.

Right. Got on the -- got on the watch list along with his mother. And apparently a Customs and Border Patrol agent was pinged that he was coming back to the country and then entered after being an extended stay in Russia. And what it shows is even when these guys are on your radar, if you don't have evidence that these guys have actually done something wrong yet and you have limited manpower, it's very hard to sort of get to the left of the boom, as they say in counterterrorism terms.

MS. RADDATZ: As one person said to me, you only have so much bandwidth when you're looking at people. And I think we, the United States, we're very much focused on the Middle East or in Pakistan, certainly not in Russia because they didn't consider it a threat.

DAN BALZ: It raises two questions. One is: how much did we actually know about him as we've combed back through all of this? And second is: did we really miss something? I mean, did -- does the post-9/11 system still have holes in it?

MR. KITFIELD: We don't know a lot so it's hard to say whether we missed something, but it's -- what I've seen so far would suggest that -- I mean, we knew these guys were -- you know, had roots in Chechnya. We know that's a conflict zone, a Muslim separatist conflict zone which is where a lot of profile fits for these terrorists.

I mean, if you look at Madrid and London, and the New York bomber, they all come from some Muslim area that's in a conflict, whether it's Pakistan or -- in (Canada ?) this week, there was two -- arrest of two terrorists attached to the Palestinian cause.

So there's -- you know, these -- this profile -- these guys fit on a profile of lone wolves who get radicalized on their own, basically have a hard time assimilating into foreign societies.

And he lived in the United States. They both lived in the United States. I mean, the brother --

MS. IFILL: The younger one was -- had --

MS. RADDATZ: Yeah. The younger one was a citizen. But focusing on the older brother in particular, I mean, there are all kinds -- there are hundreds of thousands of people on some of these lists. And, yet, a very, very small percentage, I think fewer than 5 percent are actually living in the United States legally or are American citizens. So should the FBI, should someone have kept a focus on him because he was here?

What do -- what role did the Russians play in this? Obviously, they tipped us off to him, the older brother in the beginning. Are they -- is Russian intelligence playing a role in this now or is this relying on U.S. intelligence?

MS. RADDATZ: I'm sure they're talking to Russian intelligence. And there's actually a really pretty good relationship in terms of counterterrorism between the Russians and the U.S., but something made the Russians have a red flag. And I would surmise that they probably had some sort of communications from the older brother to some sort of Russian extremist or somebody in Russia, some Islamic extremist there that concerned the Russians. And that's probably why they alerted the United States to begin with. They were probably concerned about themselves, not us, but that was -- that was a concern.

MR. KITFIELD: They've been the target much more than we have from the Chechen terrorists.

Are there other examples in these terrorist plots have been foiled or carried out our self-radicalization? We keep hearing about this.

MR. KITFIELD: Plenty. There's plenty of them. FBI has done scores of stings where they sort of pick up on the Internet that these guys are -- you know, want to launch an attack, want to get involved. They send an informant in there and sort of have -- you know, let them spin their plot and they arrest them --

MS. RADDATZ: Fort Hood.

MR. KITFIELD: -- before it happens. Ford Hood is another example.

MS. RADDATZ: Fort Hood, they say that that was self- radicalization. They get on the Internet, they learned about Awlaki, and they're inspired. And they read the magazines and then they know how to do it.

MR. KITFIELD: The London bombers actually had a connection to al-Qaida's core in Pakistan.

OK. So they weren't necessarily self-radicalized.

MR. KITFIELD: You wouldn't call them self-radicalized. Well, they were self -- they sort of joined, but then they -- the know-how was supplied by al-Qaida core, which is why the attack there was so devastating.

MS. IFILL: Well, there was another disturbing development this week with potentially wide ranging consequences. It turns out that in Syria, where tens of thousands have perished in a grinding civil war, government forces may have crossed a red line. Red line -- that color is important. This is what the president said last August.

(From tape.) We have been very clear to the Assad regime but also to other players on the ground that a red line for us is we start seeing a whole bunch of chemical weapons moving around or being utilized. That would change my calculus.

MS. IFILL: Now, this is what the president had to say today.

PRESIDENT OBAMA: (From tape.) Knowing that potentially chemical weapons have been used inside of Syria doesn't tell us when they were used, how they were used. So, you know, this is not an on or off switch. This is an ongoing challenge that all of us have to be concerned about.

This requires a little parsing. Has the calculus changed or hasn't it, James?

MR. KITFIELD: I actually think the calculus has changed. But that doesn't mean we're going to go launch an attack on the Syrian regime tomorrow or anytime in the near future.

But I think they were already leaning towards a much more assertive posture vis-a-vis the Syrian rebellion. They've doubled the amount of aid they've given to the Syrian troops on the ground fighting, including, you know, nonlethal aid like body armor and communications and medical kits. They were already doing that.

Now, they've been pushed very hard because they had this red line and it seems to have been crossed. They don't want to get pushed into going too far, too fast, but they said that no option is off the table. They're going to consult with their allies.

Well, I was at a dinner this week with the head of Qatar, who's taken the lead in supplying arms to the Syrian rebels. And he said, look -- and he had just talked to Obama the day before for two hours, and said, you know, he's gone from bullets to tanks to aircraft to rockets -- SCUD rockets, now to chemicals. He's escalating. He's testing our limits, and he's crossing all our red lines and until we do something, he'll keep escalating.

So I think there will be some move. You know, the first move would obviously be to get off the dime and actually help arm the rebels so they can take out the -- or at least protect themselves from sea and air power.

MS. IFILL: But, Martha, does it seem like a turning point to you?

MS. RADDATZ: It does not, as a matter of fact. I mean, I think it's supposed to be a turning point. And we've heard President Obama talk about this again and again, there will enormous consequences; this is a red line. But it looks to me like it's still a rather grey line. What you hear is, well, it's got to be a whole bunch of chemical weapons moving around or, today, a systematic use of chemical weapons. They definitely keep --

MS. IFILL: Kept hearing all these caveat phrases.

He does not want to go into Syria. He does not to own Syria because he knows very well what will happen if Syria is suddenly our war.

MS. DAVIS: The attacks were described as small scale, the chemical attacks. What does that mean? And what -- I don't understand what sarin gas does and where it tanks in terms of chemical weapon use on people?

MS. RADDATZ: It's a nerve agent, first of all. It basically paralyzes you and suffocates you very quickly if you have it in large doses.

Small-scale attacks -- I think they looked at two attacks. One of them I know, I believe was in Aleppo and about 30 people died. And the other is believed to be in Damascus. And I think about the same number of people. So that's what they consider small scale. But when it does it go to larger scale? If it's chemical weapons is the line, if it's using chemical weapons, what does it matter how many are killed if that's the line he has set?

MR. BALZ: Two questions. One is: what are the options that would in fact significantly escalate our involvement? What are the realistic options? And, second: to what extent has what has now happened affected the debate within the administration and kind of what's the nature of that debate?

Well, I mean, before -- we now know that Secretary of State Hillary Clinton was arguing for a much more robust response against Assad. So was David Petraeus when he was the head of the CIA. We don't really know what Kerry and Hagel are telling the president, but clearly they are being pushed towards doing more. And they're being pushed mostly by our allies, Turkey, Qatar, the Gulf States, Jordan, Lebanon. Even the Iraqis are starting to feel the spillover from all the refugees, from all the sectarian violence between Shias and Sunnis.

That fault line runs through all those countries. So they're being told very, very clearly that we need American leadership to step in here.

Now, I kind of disagree with Martha on this. I think that they will be pushed to do more. Now, I don't think it's going to be direct military action, but there's a lot you can do --

MS. RADDATZ: I think they could arm the rebels, but I don't think -- I should clarify that. I don't -- I just don't think they're going to go in there and suddenly set up --

MS. IFILL: No-fly zone?

A no-fly zone -- no-fly zones --

MR. KITFIELD: Yeah. I don't think --

MS. RADDATZ: -- sound so easy, like just don't fly here. First of all, you have to take out all the anti-aircraft.


MS. RADDATZ: You have to go in. It's kinetic. And if someone shoots -- I mean, if someone shoots at us when we're trying to take out those, then what do you do? I just think what we don't realize and we don't know here is what the strategy is for going forward. Do you just keep relying on the military? Do you just keep pushing the military as an option?

MS. IFILL: And I think one of the things you have to keep in mind too is going to be domestic pressure from Congress is going to ramp up as we keep going. Thank you both.

Now, we move on to a little politics. Seldom has the announced resignation of a single senator sent such shivers through the establishment. But when Max Baucus, a prime mover on tax reform, a renegade on gun control and one of the key senators protecting the Democratic majority said he is quitting next year, the ground shifted just a little bit. Why in this case, Sue?

MS. DAVIS: Well, there's a couple of reasons. One, I think it was a surprise. I don't think people were counting on Max Baucus to retire. The internal is that he's been a hugely consequential figure in the Senate for the better part of -- he's been serving for more than three decades, but for about the past 15 years he's played an instrumental role in passing things from the Bush tax cuts, Medicare Part D, most recently to Obama's health care law -- his fingerprints are all over that. And so from the policy he's been very influential.

And then, from the politics, he comes from Montana, a state that Barack Obama lost by double digits; is one of seven states that has a Democrat in the Senate right now that they have to defend next year. And, all of a sudden, the radars start going up again as these are the kind of states and these are the kind of races that put the Senate in play. And so --

MS. IFILL: But for the White House, wasn't he kind of a problematical ally?

MS. DAVIS: Well, this is -- this is Max Baucus. It depends on who you ask. Everyone has an opinion about him, which is also I think you saw such a reaction in Washington, because he's been around so long that there's not many people that don't have an opinion about Max Baucus and it's -- (inaudible).

MS. IFILL: Seven terms.

MS. DAVIS: In one sense, Obama may not have been able to get his health care law through without him. This is also the same senator that recently referred to the bill as a train wreck and that it was going to be problematic for consumers and --

MS. RADDATZ: So what happens without him? I mean, what about things like tax reform? What happens without a Max Baucus?

MS. DAVIS: You know -- and this has been very -- we've had a lot of Senate retirements in recent years and they always say I'm going to use my time left to do this one thing. I'm personally very skeptical that they're able to get it done.

Most recently, I think of someone like Kent Conrad, who retired in the last cycle and was the budget chairman, and said, I'm going to spend my two years getting a fiscal deal. Well, we know how well that worked out.

The idea that chairmen as lame ducks have a better chance of moving sweeping legislation as they wave goodbye to their colleagues and walk out the door is going to be a very tall ask.

And didn't voting against the background checks, didn't that sort of wear out his welcome with a lot of Democrats?

MS. DAVIS: And Baucus has always been -- he's always infuriated liberal Democrats. The health care bill is a great example because liberals that wanted universal health care, he may -- he was made sure that they -- and they didn't have the votes to do it.

So when he announced his retirement, there was a pretty loud cheer that came from the more progressive side of the Democratic Party, who are angling very hard for Brian Schweitzer, former governor of Montana, to get in and run for that seat. Schweitzer, who has a pretty high national ID level and made a splash -- I believe it was in 2008 -- at the Democratic convention and gave a very sort of populist, crowd-pleasing speech. And they think --

MS. IFILL: And who's in line to be the head of the -- the next head of the finance committee, a populist, Ron Wyden of Oregon.

MS. DAVIS: Ron Wyden. Yes.

MS. IFILL: So they've got to be cheering that as well.


MR. BALZ: Does this -- does this genuinely put the Senate more at risk?

MS. DAVIS: Yes, in the sense that it's a conservative state; no, in the sense that you can't beat somebody with nobody. And I think Republicans have a very thin bench in Montana. There is no obvious candidate that's going to run there. I know that Republicans will say that this is a very conservative state, but it hasn't elected a Democrat to the Senate since 2000, sort of one of those states that tends to vote conservative nationwide but has progressive leaning statewide. West Virginia is another good example of a state like that.

: Well, eight senators are retiring. Six of them are Democrats, right? So Democrats are the ones who have a more difficult time defending their turf in 2014 than Republicans do. So what are they doing about that?

MS. DAVIS: Well, you know, a lot of this is roll the dice. The Democrats have had back to back election cycles where they're just defending more seats. It's just the math is not in their favor. There's 33 seats up this -- next year. Twenty-one are Democrats. And a lot of them are in red-leaning states.

I do think that, at least based on the 2012 model, it's a little too early because we don't have a lot of candidates in these races yet. They put a very high premium on recruiting really strong candidates early. Obviously, both parties do that, but they'll oftentimes look for people that are already well known in the state, maybe have already held a statewide office, and can raise a lot of money.

MS. IFILL: Like Brian Schweitzer say. But I'm also curious in the end what it is that the Republicans do. Do they just sit back and cross their arms, and say, happy days are here again or do they also try to find strong candidates to grab those seats aggressively?

MS. DAVIS: Well, the problem that Republicans have had is that the majority is within their grasp for at least two cycles.

And their own candidates have cost it to them, the best reference for the last cycle would be Todd Akin, recruiting candidates that maybe can win primaries but are -- alienate a general election audience. So they are having their own sort of internal struggles between the more conservative wing and more mainstream and that battle still needs to play out in a lot of these states.

MS. IFILL: Oh, what fun we're going to have in the midterm elections.

We'll it's not often that we get a peek inside a meeting of the Presidents' Club, as our friend, Michael Duffy, called it. There are only five of them. And along with their wives in Dallas this week, they provided one of the most interesting tableau of democracy that we ever get to see. Plus the remarks at the opening of George W. Bush's presidential library reminded us how very different they are.

PRESIDENT H.W. GEORGE BUSH: (From tape.) Those who made this marvelous museum possible, we thank you especially. And we're glad to be here. God bless America. And thank you very much.

PRESIDENT BILL CLINTON: (From tape.) People began to joke that I was getting so close to the Bush family, I had become the black sheep son. My mother told me not to talk too long today. And, Barbara, I will not let you down.

PRESIDENT OBAMA: (From tape.) To know the man is to like the man, because he's comfortable in his own skin. He knows who he is. He doesn't put on any pretenses. He takes his job seriously, but he doesn't take himself too serious. He is a good man.

PRESIDENT GEORGE W. BUSH: (From tape.) One of the benefits of freedom is that people can disagree. It's fair to say I created plenty of opportunities to exercise that right.

MS. IFILL: You were there, Dan. And President Bush ended that a little teary. It was quite a day. What was most striking to you?

MR. BALZ: Gwen, there were several things that were striking, not all necessarily related. The first is when you see that group of people there on the stage, you are reminded of how much history they represent, wars, recessions, scandal, success, failure. Each one of those people on the stage has experienced some or all of those. You're reminded that they shaped history and they were shaped by history.

The second is, in the sort of personal interaction, you highlight they are different. They are different people and they have different ideologies. And yet, there is a respect and in some ways, genuine friendship among them.

President Obama made the comment that until you are behind the desk in the Oval Office, you don't fully understand the burdens. Everyone on that stage understood those burdens, understands them today, and they have some appreciation of what each of them went through, even if they might not have agreed at the time or since with all that they did.

The third was simply the role that the Bush and Clinton families have played in our political life over the last three decades and may play in the future.

MS. IFILL: Describe the museum. Did you get to go inside?

MR. BALZ: I did. I took a tour a couple of weeks ago. Architecturally, it's a very handsome building. Laura Bush had an influence in and out in terms of the architecture, and the Texas landscape that they've created around it. It's a very handsome place.

The museum is very much a reflection of George W. Bush. He has said, I'm content to let history judge me. And you go through the museum, it's straightforward. It's unapologetic. And yet, there is a second of it called the Decision Points Theater, in which you can go in and second guess George W. Bush. You can say I disagree, and he'll come on and say, well, here's what I did and why I did it.

What do you think he thinks? I mean, I know he wants history to judge, but do you get a sense from listening to him, from being down there what he really thinks his own legacy will be?

I think he thinks it will be better than it was when he left office.

And it usually is, isn't it, for most presidents?

MR. BALZ: It usually is.

MS. IFILL: I mean, look at Bill Clinton.

Right. I mean --

But Bill Clinton didn't have that war.

I think the real question is how the Iraq war is judged in history. You know, he had the Iraq war. He had the financial collapse in his last few months. Hurricane Katrina -- there were a number of things that, as he left office, made him a very unpopular president and one who was judged harshly as he left.

People around him believe that there is a fuller story to tell and that the museum itself doesn't do that. But it sets in motion an opportunity to look at him more broadly, some of the other things that were mentioned by the other presidents -- his initiative on HIV/AIDS and Africa, for example, the fact that he advocated for comprehensive --

Was pretty amazing. Really --

MR. BALZ: Hugely significant. The fact that he advocated for immigration reform, was defeated by his own party on that. His own party has begun to come around and approach that issue differently. So I think they believe that over a long period of time, there may be a reassessment.

MR. KITFIELD: Your paper reported that the relationship between him and President Obama remains fairly cool. I think maybe that's inevitable, given how strongly Obama was against the Iraq War and how much of it defined President Bush, but did you pick up on that sort of coolness as well while you were there?

MR. BALZ: Well, on a day like this, that's all hidden away. I mean, this was a day to celebrate the opening of the library, to pay tribute to George W. Bush and every president did that. But there is no question that that's not what you would call an ongoing healthy relationship.

What do you think Bush's legacy is for the Republican Party?

MR. BALZ: It's a really interesting question and one that's undergoing some debate right now. Because of immigration, for example, there's a part of the party that is saying, you know, the compassionate conservative message of 1999 and 2000 is one that we could -- should embrace and we would do better if we did.

On the other hand, there are people within the party who still believe, A, that because of his unpopularity as he left office and, B, because of the decisions he's made, he's still something of a toxic figure in a general election sense. And they want to stay away from him.

So the story is still being told about him and probably about all of the other members of the club as well. Thanks, Dan. And thanks to everybody else as well.

We've got to go for now, but the conversation will continue online on the "Washington Week Webcast Extra," where, among other things, we'll talk about the health care bill you didn't hear about this week and why it failed. We stream live at 8:30 p.m. Eastern at Keep up with daily developments with me on the PBS "NewsHour." And we'll see you again next week on "Washington Week." Good night.