To the fight against cancer. And mounting concerns over Climate Change. We reached this kind of unfortunate milestone, 400 parts per million of car done carbon dioxide. And that number is something this planet has not seen in millions of years, not in recorded history. Sreenivasan those are just some of the stories were covering on tonights pbs newshour. Major funding for the pbs newshour has been provided by and by the alfred p. Sloan foundation. Supporting science, technology, and improved Economic Performance and Financial Literacy in the 21st century. And with the ongoing support of 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. Sreenivasan the death toll reached 31 today in the russian city of volgograd, after the second suicide bombing in as many days. The first came sunday at the citys main train station. The attacks raised new security concerns, just over a month before russia plays host to the Winter Olympics. Well hear more on the bombings and olympic security after this news summary. East african nations have agreed to defeat a rebel leader in south sudan, if he rejects a ceasefire. The president of uganda delivered that message during a visit to south sudan today. He said neighboring states gave rebel leader riek machar four days to respond or face a wider conflict. Meanwhile, the u. N. Estimated today that up to 180,000 people have been displaced since ethnic clashes began in middecember. At least 1,000 others have died. New trouble erupted in congo today. The state television station, airport and main military base in the capital city, all came under attack. A government spokesman in kinshasa said the attackers were armed with machetes, sticks and other weapons, but they were driven back by government troops. The government calls the population the victim of this terrorist attack because there were so few attacks and weapons, we think their purpose was to terrorize the people on the eve of new years eve celebrations which are very important in our culture. Sreenivasan the government said the attackers were followers of a selfstyled evangelical prophet. The assault touched off gun battles that left at least 40 people dead. In western iraq, police tore down a sunni protest camp today after protesters agreed to end their monthslong demonstration. The camp was in ramadi, in anbar province. Sunnis erected it to protest what they see as discrimination by the shiite led government. Meanwhile, clashes near the sit in site today left ten people dead, including gunmen and three policemen. The government of afghanistan is rejecting a u. S. Intelligence finding that many of the gains there could be lost by 2017. In kabul today, a spokesman for President Hamid karzai called the assessment baseless. The National Intelligence estimate is the work of 16 u. S. Agencies. It also says afghanistan could descend into outright chaos if theres no agreement to keep some u. S. Troops beyond 2014. The latest attempt to reach a russian ship trapped in Antarctic Ice was called off today, in the face of a blizzard. An australian icebreaker had been sent in to rescue 74 people whove been stuck on board the russian vessel for a week. The icebreaker was ordered to turn back due to poor visibility. The icebreaker plans to resume its mission as soon as the weather improves. The teenager who attacked a denverarea high school meant to claim many more victims than he did. Authorities gave that assessment of 18yearold karl pierson at a News Conference today. Pierson opened fire at Arapahoe County high school on december 13. He shot one student, who later died of her wounds, before killing himself. The sheriff says pierson had a 12gauge shotgun, three molotov cocktails, and more than 125 rounds of ammunition. His intent was to use as many of those rounds as he possibly could. And use the molotov cocktails in the most destructive manner that he was able to do. He was bent on evil. And he was bent on causing the largest amount of harm to the largest number of people that he could sreenivasan the sheriff says pierson got in through a door that was frequently propped open. Six states have been chosen to develop test sites for unmanned, commercial drones. The federal Aviation Administration announced today its chosen alaska, nevada, new york, north dakota, texas and virginia. Theyll Host Research sites and try to develop operational guidelines over the next two years. The f. A. A. Projects 7,500 commercial drones could be flying over the u. S. Within five years after gaining widespread access to the air. Wall street was relatively quiet on this nexttolast trading day of the year. The Dow Jones Industrial average rose nearly 26 points to close at 16,504. The nasdaq fell two points to close at 4,154. Still to come on the newshour two bombings in two days for one russian city; how the Nuclear Talks are playing inside iran; the fight in hawaii over genetically modified seeds; miles obrien on the years big science news. Plus, what the 2012 election tells about 2014 and politics moving forward. Sreenivasan now back to russia, where a pair of bombings have rocked a city in the countrys southeast this week. No one has claimed responsibility in the attacks and there are worries that they may intensify as the start of the socci winter Olympic Games comes closer. Bomb technicians and investigators in volgograd combed through the charred remains of a trolleycar. Hours after a suicide bomb packed with shrapnel ripped it apart during monday morning rush hour. translated i heard it, i live here in the courtyard, i had just started the engine of my car. And i noticed that my wheel was flat. I went out and felt the blast. The ground was shaking, and the windows of the car were shaking. I thought at first that maybe it was a tire exploded or sreenivasan a day earlier, a woman blew herself up at volgograds main railway station, killing 17 people. Closed Circuit Television captured the moment of detonation outside and inside the station. Today, russias main Investigative Agency said the two bombs were similar, and likely the work of the same group. translated according to preliminary information, the explosive device on the trolley bus was at least the equivalent like the explosive device at the train station, it was stuffed with shrapnel and because the shrapnel was identical in both explosive devices, this confirms to the investigators that the two terrorist acts were connected. Sreenivasan a state of emergency has now been imposed in volgograd and authorities have stepped up security at train stations across russia. translated i want to stress that because of these events according to the decision all departments were put under a regime of high alert across the whole country. Sreenivasan volgograd was also hit last october by a bus bombing captured on video that killed six. The Southern City is the former stalingrad, and a key transportation hub for russias restive north caucasus. The region includes dagestan and chechnya, where muslim separatists have long sought independence. The city is also about 400 miles northeast of sochi, where the Winter Olympics will be held in less than six weeks. Last july, Chechen Rebel leader doku umarov threatened to strike civilian targets across russia, including at sochi. The government has employed extraordinary measures, including the use of elite forces, to protect the winter games. But after two bombings in two days, some in volgograd have their doubts. translated i think that of the people standing here, no one would tell you that they feel safe. A lot has been promised, but little has been done. Its clear, everyone can see it. Even so, the head of the Russian Olympic Committee voiced confidence today. He said, everything necessary has already been done. Joining me now to discuss who might be behind the attacks, and the security situation surrounding the upcoming Olympic Games are andrew weiss, a director for russian, ukrainian and Eurasian Affairs on the National SecurityCouncil Staff during the clinton and george h. W. Bush administrations. Hes now a Vice President at the Carnegie Endowment for international peace. And Brian Jenkins has been a Security Consultant for major sporting events including the olympics and the world cup. Hes a terrorism expert and Senior Adviser at the rand corporation. I want to start with you. What organization could be behind these attacks . You were also telling me that perhaps yesterdays bomber wasnt a woman, there is more information coming out. Everything we know right now is very fragmentary. The accounts sub that the bomber from sundays attack on the train station is a russian, ethnic russian convert to islam who comes from the russian heartland who moved to the dagestan region to join the fighters there. At this point there is no information about who is responsible for the trolley bus attack earlier today. So Brian Jenkins i want to ask, when we think about these large sort of events like the olympics and some event like this proceeding that, how does russia prepare for it . Well, security has become an extremely important part of olympic planning, ever since the munich attack in 1972. And security has come to really be a dominant issue. We saw enormous security for the beijing olympics and in 2008 and for the london olympics in 2012. By now all of the security measures would have been in place in sochi. Those would include measures to protect the actual venues, the sitesofthe events themselves, measures in place to protect the participants in those events, both the athletes and the officials, as well as measures to protect the spectators who will be coming to view the events. Andrew, if all of this emphasis has been on sochi, does that leave the rest of russian russia unprotected and possibly targets for i guess insurgents. I think there is no doubt that the russian can do good site security k protect important targets, there is no doubt there a Strong Security presence but you go to any major russian train station, there were machines set up to scan your luggage, people just breeze past, i have never had to put my bags in recent memory on those kinds of scanning devices, so i think the country abounds in soft targets. I think the rebel groups that are interested in embarrassing the regime ahead of the Olympic Games are likely to be looking for places where the security presence is either poor or minimal. So Brian Jenkins i have to ask, russia has been dealing with this sort of low level insurgency for years now, why havent they been able to stamp it out . Well, you know, the conflicts in the caucuses go aback centuries h shall this is a long narrative of an area that has been conquered by but never entirely pacified by russia. What we saw recently are two nasty wars. That has, that has activated an increasingly islamist character of the insurgency itself stamping out a group like this, it takes often takes decades. We do see examples around the world where terrorists campaigns have gone on for scores of years. Andrew weiss, the timing of this there is clearly a point to this. This is something that some of the opposition have been saying out loud. We are planning to attack something near sochi if not sochi but theyre making a statement just by the timing of this, right. I think the timing is dreadful. The russian public are on their way to the biggest holiday of the year which is new years, to create an atmosphere of panic throughout the russian body politic is a big deal. If you went to moscow would you have seen strations being evacuated, random searches, it created a sense to people there is a real threat, a live threat and authorities will be struggling to head it off. So Brian Jenkins considering that the eyes of the world are going to be on sochi, what sorts of measures have the russians taken . There have been reports that they have essentially almost sealed off the city or they will seal off the city almost a month before the games. Well, that is certainly their goal. They are going to try to turn the entire city of sochi into the security equivalent of ben gurin airport in tel aviv. And so there will be multiple checks, something thats new at this olympics that we havent seen before are the credentialingly of the spectators themselves h that is people who buy tickets go online to buy these tickets, receive a credential and that will become a way of verifying their identity at the entry to each one of the each one of the venues. In addition they have introduced a system that will enable them to monitor every telephone call, every email message, every form of electronic conversation, Electronic Communications in sochi will be not only monitors but they will have the ability to intervene and modify the messages themselves. Beyond that, though, i mean look, you can defend a piece of territory, protect a piece of territory for a period of time. But if the terrorists have virtually unlimited targets across russia, what youre concerned about is either that there are people already in sochi that have already infiltrated, and there are prepositioned weapons or devices in sochi, and the russians have reported that they have busted up some plots where there have been prepositioned material, at least close to sochi, or you worry about an attack that will be concurrent to the olympics but in another part of the country, but that nonetheless will cause embarrassment. One of the greatest concerns is that we will see Something Like a nairobi Shopping Mall attack or a more ambitiously a mumbai attack or like some of the major hostage seizures that weve seen carried out by the chechens before, with demands to suspend the olympics. So andrew, how much do the politics of vladimir puttin and his tactics now play into this situation . I think the russian tactical playbook has been consist enover the past 15 years. In the case of chechnya they pacified that country with the aid of a local war lord. So they basically said anyone who is religiously on serve ant who is not fitting the standard profile of a peaceful citizen, are you in our sights. In dagestan they have a total mess on their hands, where you have a conflict with three or four layers there is tremendous youth unemployment, radicallization, there is a fight in terms of two different strains of islam, and a very heavyhanded security response. So in many ways the russians have created this problem, they have found no solution to fix it. Andrew weises from the Carnegie Endowment of peace, brian yen kins, thank so sos jenkins thanks so much for your time. Sreenivasan iran, the United States and other world powers met today in geneva to hash out the practical details of the deal signed last month, which suspends key elements of the islamic states Nuclear Program in exchange for limited sanctions relief. Much has been reported about objections to the deal and threats of new sanctions by some in the u. S. And some american allies. Much less is known about how the interim agreement and prospects for a full agreement are playing inside iran. Tonight, Jeffrey Brown takes a closer look at that side of the story. Brown david ignatius, Foreign Affairs columnist for the washington post, recently returned from a reporting trip to iran, where he looked at perceptions and opinions surrounding the countrys negotiations with the west. He joins me now. Welcome back. Thank you. Brown you saw a lively debate within iran about this deal. Explain what you saw and how did the sides divide. I was in iran for four days, not a long time so i dont want to pretend that i have any kind of comprehensive view. But i did manage to see representatives of the most pragmatic, pro negotiation wing, the foreign minister zarif and one of the hardest line people close to the Supreme Leader, a man name the hughes ann maduri who was the editor of the big conservative newspaper. These two spoke about the negotiations over the Nuclear Issue with the United States and other countries in such different terms. And what was fascinating to me was the pragmatist zarif and the hardliner maduri each spoke as if they were talking for the Supreme Leader. Both. Brown they dote both cannot be true. And so i had a sense, some of this im sure is a show for the west, you know, the two factions, it is a classic negotiating techniquement but i think there are real and fundamental differences. Brown you reported that some hardliners believe that zarif even misrepresented the enrichment part of the deal to comaini. I was told that specifically by the hard line editor who said to me when i asked him why did you agree to the interim deal if you think it is such a bad idea. Said well the foreign minister zarif called president rouhani, the new president , in the middle of the night from geneva an gave him an account of what was in the deal. And he on that basis wrote a letter to the Supreme Leader chomeini and he then said this gentleman was not correct in what he said. Specifically on the question of whether the deal provides iran with a right tone rich uranium as it has always claimed it must have for an