we might see chaos. >> woodruff: plus we examine the role of the egyptian military in the uprising and in the transition to a new government. >> ifill: then science correspondent miles o'brien reports on the threat posed by dirty bombs made of radioactive material. >> as the terrorists are trying to think of new ways to access materials we're trying to think of new ways to protect them. >> woodruff: jeffrey brown talks to transportation secretary ray lahood about a government probe into toyota's troubles. >> ifill: and we look at the safety of municipal bonds and the risk that some cities could default on their obligations. >> woodruff: that's all ahead on tonight's newshour. major funding for the pbs newshour has been provided by: >> oil companies have changed my country. >> oil companies can make a difference. >> we have the chance to build the economy. >> create jobs, keep people healthy and improve schools. >> and our communities. >> in angola chevron helps train engineers, teachers and farmers, launch child's programs. it's not just good business. >> i'm hopeful about my country's future. >> it's my country's future. >> you can't manufacture pride. but pride builds great cars. and you'll find it in the people at toyota all across america. >> pacific life. pacific life-- the power to help you succeed. >> and by bnsf railway. >> the william and flora hewlett foundation, working to solve social and environmental problems at home and around the world. and with the ongoing supporort f these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: an estimated quarter-million egyptians flooded back into central cairo today, injecting new energy into the two-week-old protests. the huge demonstration came hours after newly named vice president omar suleiman announced new committees to oversee constitutional changes and presidential term limits. we begin our coverage with this report from lindsey hilsum of independent television news. >> reporter: the crush was intense. it was almost impossible to move. tens of thousands of people streamed into tahrir square. ignoring the vice president's announcement that a timetable for the transition of power had been laid out, determined to keep on demonstrating. the government was clearly hoping that the momentum would have gone out of these protests. but the crowd here today is as big as any we've seen. the people i've been speaking to say they feel secure to come to the square at the moment because they've seen no violence for the past couple of days so that leaves the regime with a dilemma: to crack down again or let it keep on growing. some told me it was their first visit. only now have they plucked up the courage. >> my first day coming. >> reporter: why did you decide to come for the first time? why not before? >> before i heard it was like chaos. a lot of people were getting hit and stuff. today i actually went to express my feelings on everything. >> i am not sure that i am able to come. i was somehow afraid. i feel it's safe and very secure. >> reporter: many were hoping for an appearance by way of a google executive and facebook protest organizer. last night he made an emotional appearance on tv after being released from 12 days in prison. the interviewer showed him photographed with some who were killed in the protest. he was overwhelmed. in prison he had no idea of the size of the movement sparked by a facebook page that he started. nor the violence or the attempt to put it down. >> in egypt we like to make heroes. i'm not a hero. i was sleeping for 12 days. the heroes are the ones who were beaten, who were out there in the streets, the one who sacrificed their lives. what happened to me just makes me regret that i wasn't with the people. >> reporter: as a cacophony of diverse voices sound through the square some are touting mr. goen even as a potential leader of this huge crowd. >> we need a symbol that everyone agrees on. we need a consensus. he's honest. he's very well educated. >> reporter:. >> i saw him today on the tv. i saw how he believes in this country and how he loves his country. >> reporter: the leader they still haven't managed to bring down, president mubarak, was shown meeting the foreign minister of the united arab emirates. his vice president left to reassure the country that there will be no more state violence. will it end? >> ifill: thousands of people also demonstrated today in several other egyptian cities. in cairo, the enormous crowd in tahrir square lingered long after sundown. the site was still packed as midnight approached. now to margaret warner's report from cairo. she sat down with cal tech professor, an egyptian-american nobel prize winning chemist and one of several unofficial mediators between the egyptian government and the young tahrir square organizers. >> warner: dr. zewail, thank you for joining. >> a pleasure. >> warner: here we sit tuesday two weeks since these demonstrations started. you have the protestors in the square. you have the government holding these other meetings. you're kind of shuttling between them. is this negotiation for real? >> well, i guess your first question is a good one because my level of optimism... by nature i'm an optimist but my level of optimism has been going up and down and up and down. it seems to me that it's very clear that the young people are demanding a major change. they are not really talking about superficial or cosmetics. and therefore the business as usual is just simply not accepted to them. but what they really want to see is a new egypt. >> warner: at least publicly the protestors in the square are saying mubarak must go now, period. then they have a laundry list. the government is saying no, mubarak and suleiman are going to run this transition until the elections. are both sides being inflexible here? >> i think the reason the... you say... that the youth say for president mubarak to depart now is because there is a mistrust with the system. what they don't want to see is the same status quo in order to make it appear different. from my point of view what i'm trying to... my role is to say also to the government there should be an immediate action and real action. if we have a substantial action coming in, maybe the... these young people then will listen to the people that we trust. but i don't think you can do it as a tranquilizer. really the response from the government should be immediate and very clear. >> warner: give us an example. something that president mubarak and vice president suleiman could do right now that would say to you and to egypt and to these young people, we really are going to make fundamental change. >> one thing that is really clear to me is to immediately, immediately stop the martial law, for example, in the country. everybody is bothered by this. there is no reason for egypt to-- it's a great civilization-- to be under martial law. secondly, the constitution, for example, there are certain articles in the constitution. it's not acceptable to me. it's not acceptable to the youth. it is not acceptable to the egyptians who want to see a new life. and i would think that this immediately has to change. these articles which basically were not... would not allow anybody to run to be a president. the last election in the parliament, for example, was close to 90% from the governing party. >> warner: 97% i think. >> right. so these concepts if transformed immediately and by immediately i mean week time. i'm not talking about six months time. >> warner: what's the risk if this doesn't happen quickly? >> i think the... they are so determined and they will continue and i think that it is not good for egypt from the point of view of the economic problem to a large part egypt depends on, for example tourism, investment. then you have the issue of security also. my worry is that there will be a tipping point at which all of this would be gone and we might see chaos. >> warner: meaning it could spin out of control. >> yeah, yeah. >> warner: now, vice president suleiman said in an interview on abc on sunday, egypt would have democracy, he said, when the people have the culture of democracy. implying they don't. >> there are people who believe that you can't have democracy in certain cultures. i just like to remind people about egypt over the last 100 years. egypt had the first constitution in the middle east that allowed for liberty. it had democracy. so i think this is not right to say that the people are not ready for democracy. everybody in the world is ready for liberty. it's a question of how you do it. >> warner: now the government has taken certain steps. do you see a commitment on the part of the government, even if maybe not at the pace you're suggesting but to get to a full democracy or do you think as the protestors think that they're just stalling, buying time. >> the changes are fine and it's okay. as of this morning they are continuing with some changes. but if you... if the people of egypt want to change a system, that's different. i think that it is not a personal fight with mubarak. it is actually a fight for a new democratic egypt. and the changes in many ways are slow or superficial. it's not going to satisfy the egyptian mass. >> warner: you think that's what's happening now? >> i think it's too slow. therefore, my advice is to do that in this very critical for history's sake and for really his legacy sake to do it promptly and swiftly and in a very, very clear way. >> warner: you are egyptian and american, dual citizen. is there a coherent message? do you hear a coherent message from washington and what do egyptians you speak with-- and you're speaking to all the big players-- what are they hearing? >> this is an egyptian problem. it is not an american problem. i don't think that the egyptians in this particular case is looking at the american government to come here and help them in tahrir square. i think what america can do is to maintain a consistent policy of saying we are friends, would like to be friends of egypt, and we would like to support liberty in egypt. >> warner: do you hear that consistent policy? >> the liberty issue, i do hear it. the key thing here really is not to interfere too much. >> warner: as you know, the big concern in many quarters in the united states is that if egypt has a fully open system that the muslim brotherhood, an islamist group will, in fact, gain all kinds of power here. what do you say to that? >> there is too much exaggeration about the issue of the muslim brotherhood. i think in a democracy, in a true democracy where they can speak and they are not underground and they are not fighting, the egyptian people will either accept them or not accept them. if they are really in a country that follows the rule of law, then i don't believe we will have a problem. including elections, including the parliament and so on. >> warner: so you think there's nothing to fear? >> no. i can see that certain groups will have a much stronger influence. but suppose even that they are stronger at that point, i can tell you that the majority of the egyptians i know, they think of a much wider spectrum of people than the muslim brotherhood. so i don't think... i think the key here in this equation is egypt being... making the transition to democracy. if it's a true democracy i'm not worrying. on this note, i think president mubarak would be the first egyptian or the first arab leader to the biggest country in the arab world, that he will be witnessing the changing of the guards. >> warner: as opposed to being in exile. >> correct. >> warner: thank you so much. >> thank you, margaret and welcome to egypt. >> warner: thank you. >> ifill: that interview took place before the government's announce to creating committees to changing the constitution which this evening dr. zewail told margaret that they were not enough to meet the people's demands. but the government can't put up with long-term protests. >> woodruff: more on egypt coming up with a look at the roleate country's military. plus, the threat of dirty bombs; the investigation into toyota's recalls; and the troubled municipal bond market. but first, the other news of the day. here's hari sreenivasan. >> sreenivasan: churches and a court came under attack from a muslim mob in indonesia today. it all happened on the island of java, some 250 miles from the capital, jakarta. hundreds of men, many wearing muslim prayer caps or scarves, hurled rocks at a court building and pelted riot police. they also attacked three churches, setting some on fire. the mob was demanding harsh punishment for a christian who's on trial for blasphemy. president obama has revived his call to build a high-speed rail system at a cost of $53 billion over six years. the goal would be developing trains that travel up to 250 miles an hour. the program would also tie existing rail lines to new projects. vice president biden announced the effort today in philadelphia. if we do not take this step now, if we do not seize the future, you tell me, you tell me how america is going to have the opportunity to lead the world economy in the 21st century like we did in the 20th? we cannot settle. we're determined to lead again. and this is the beginning of our effort to once again seize the future. >> sreenivasan: the initial $8 billion in spending is part of the president's budget for the coming fiscal year. it's being released next monday. on wall street, trading was relatively light, but stocks still managed another advance. the dow jones industrial average gained 71 points to close at 12,233. the nasdaq rose 13 points to close at 2797. a new breast cancer study could trigger a major change in treatment. researchers found that for those women in early stages of the disease, and with only limited spread, there is no benefit to radical surgery to remove many lymph nodes. the surgery can have serious side effects, but it's been standard medical practice for decades. the new findings have already been adopted by several major cancer centers. the study was done for the national cancer institute. those are some of the day's major stories. now, back to gwen. >> ifill: and we come back to egypt. the country's future may depend on what role the egyptian military plays in the political world order. at the pentagon today, defense secretary gates had only praise for his egyptian counterparts. >> i think that the egyptian military has conducted itself in an exemplary fashion during this entire episode. and they have acted with great restraint and frankly they have done everything that we have indicated we would hope that they would do. >> ifill: but is the military in a position to do what protesters are hoping for? for that, we turn to shibley telhami, the anwar sadat professor of peace and development at the university of maryland. and matthew axelrod, who served as north africa and egypt director at the pentagon from 2005 to 2007. welcome to you both. we heard what vice president suleiman said this afternoon about not being able to put up with continued protests. we know that he is close to the military. so what connection is there here between the military in egypt and the outcome everyone seems to be hoping for? >> well first of all the military really is the anchor of this regime. it's always been that way since 1952 with the overthrow of the monarchy but it's even become more so in the past two weeks. mr. suleiman himself comes out of the military. he's considered one of them. defense minister is one of the most influential men in egypt for the fast 20 years, just been promoted to deputy prime minister. the prime minister who was promoted also from the military the president himself is out of the military. this is the anchor of the regime. they're protecting their interests so people see them as the regime versus the military. the military is part and parcel of this regime. obviously they may feel differently about the person of the president if they want to protect the institution. now i think the institution of the military is respected in egypt for a variety of reasons. they have been since 1952. it was really a brief period in which there was a joke in egypt between the defeat in 1967 and then the highly credible performance in the '73 war. but in general they're respected. they don't want to lose that. in the short term, clearly they play on that because when the security services were playing the bad guys in essence, they were confronting the demonstrators we now know in fact they were behind some of the thugs. and the military inserted itself seemed to stop the attacks and play on the loyalty of the public. but there's coming a point where the choice is going to be between remaining loyal to the institutions that they now have and alienating the public. they know in the future they want to be part of any system in egypt. they don't want to go too far in alienating the public. >> ifill: how much can the military if it is indeed the anchor of the system as the professor says, how many can they be an agent of change at a time when we see none of the discontent is fading. >> i actually don't think that the military egyptian will be the primary agent of change in egypt. i think that will have to be the egyptian people and the people in tahrir. and the egyptian military will be affected by that. i agree with dr. telhami that they have interests that they are interested in protecting. when we're thinking about who will be the primary agent of change and who the actors are going to be i think it will be primarily the egyptian people. whether or not they continue to rally as they have. and do so defiantly. that will really be the key factor. what's happening right now... i'm sorry. >> ifill: go ahead. >> what's happening right now is the regime is bringing out incremental concessions, and they're trying to see whether or not these incremental concessions will be enough. and so far they haven't been. so it's a back-and-forth between the protestors and the regime. >> ifill: how much, i'll ask you this and then i'd like to ask professor telhami as well, how intertwined is the political structure in egypt, whether it's in the person of mubarak or anyone else with the military structure? are they inseparable? first to you, mr. axelrod. >> i think that they are inseparable behind the scenes. what's interesting is dr. telhami said that the egyptian military maintains a great deal of credibility and a respect. this is precisely because they are not tied up with a daily repressive apparatus of the mubarak regime and have not been for some time. they had been depoliticized by first president sadat and then president mubarak. because of that they actually are very important political actors in times of crises such as right now. but mainly they play a behind- the-scenes role. for the first time that role is coming to the fore. not necessarily with the uniform military but also the expanded military community of retired officers. that is who we see right now in the leadership of the current mubarak presidency. >> ifill: do you agree with that, professor? >> up to a point. there's very little separation with the president. let's put it this way. in the past several years or before even this crisis, the president can have an important strategic meeting in the morning it will be the defense minister and then with them omar suleiman who is the head of intelligence and now the vice president. those were the two most important people with whom the president met on a regular basis. so they're inseparable from the president. in society, he's right about they're not being particularly visible in the same way like the business people who are very tied into the regime and the national democrati