corporate funding is provided by mutual of america-- designing customized individual and group retirement products. that's why we are your retirement company. additional support is provided by: and by the corporation for public broadcasting and by contributions to your pbs station from viewers like you. thank you. from the tisch wnet studios in lincoln center in new york, hari sreenivasan. >> sreenivasan: good evening. thanks for joining us. secretary of state john kerry traveled today to cairo to try to enlist egypt's support in what the white house describes as america's war against the islamic state, also known as isil. egypt is the most populous country in the arab world. >> it will be our goal in every meeting that we have on the international basis, together, working to degrade and ultimately to defeat isil. >> sreenivasan: in his weekly radio address, president obama also emphasized the need to build an arab coalition to fight the extremist group, which has seized significant portions of syria and iraq. but the president cautioned: >> to meet a threat like this, we have to be smart, we have to use our power wisely, and we have to avoid the mistakes of the past. >> sreenivasan: the iraqi prime minister, haider al-abadi, said today that he has ordered the army to stop shelling populated areas held by the islamic state to help reduce civilian casualties. the group controls a number of iraqi cities, including mosul, tikrit and fallujah. we'll have more on isis in a moment. it's the last weekend before scotland's historic independence referendum. and in edinburgh today, demonstrators turned out who support keeping scotland in the united kingdom. the most recent polls show those supporting scottish independence trail by a narrow margin. the vote is thursday. turning now to ukraine, where, despite the recent cease-fire, the government says its forces repelled an attack by pro- russian rebels at the airport in donetsk. nearby, in luhansk, a convoy of more than 200 russian trucks crossed the border to deliver food to that rebel-held city of 400,000. thousands of residents there have been without water or electricity for several weeks. today, ukraine's prime minister expressed pessimism about a peaceful resolution to the crisis. >> let me put it bluntly, we are still in the state of war, and the key aggressor is russian federation. >> sreenivasan: law enforcement officials from three states converged on a location in northeastern pennsylvania overnight after two state troopers were shot outside their barracks. one trooper was killed and the other wounded. the incident occurred in blooming grove, pennsylvania. police are questioning a 48- year-old man described as a person of interest. no arrests have been made. with less than two months until election day, a federal appeals court has reinstated a wisconsin law requiring voters to show a photo i.d. at the polls. a three-judge panel issued the ruling yesterday. last april, a lower court found the law unconstitutional, saying it posed an unfair burden on poor and minority voters. more than 30 states have some form of voter i.d. law on the books. the national football league now acknowledges that up to a third of its retired players could develop long-term cognitive problems, many at what it describes as "notably younger ages" than the general population. the disclosure was made in papers filed in federal court in connection with the settlement of a lawsuit brought by former players against the league. adrian peterson, one of the n.f.l.'s biggest stars, has been indicted in texas on child abuse charges. he allegedly used a branch to spank his four-year-old son. the child reportedly suffered numerous cuts and bruises on his back, legs, buttocks and scrotum. peterson's lawyer says the minnesota vikings running back never intended to harm the child and said pq+imon had been disciplined the same way when he was growing up. and for 13 years, no one knew what happened to the people in this photograph, which was found at ground zero a month after the 9/11 attack. each year, lesley university professor elizabeth stringer keefe posted the picture online hoping to solve the mystery. finally, this week, a network of boston blogs wrote about her search, and more than 70,000 people retweeted the photo. on friday, one of the people in the photo saw it and came forward. turns out, fred mahe was on the 77th floor of the south tower on the day of the attack and his photo was lost. the good news is that everyone in the picture is alive. mahe wrote, "on september 11, we remember what we lost." on september 12, we remember what we have." >> sreenivasan: for more about the war on the islamic state, we are joined now by austin long. he is a professor at columbia university's school of international and public affairs. previously, he was an adviser to the multinational force in iraq. so there seems to be in public opinion polls support for air strikes but not for ground troops. and that seems to be the plan that the president is following at the moment. how effective can air strikes be without intelligence on the ground that can verify what's happening and factor more intelligence on whether you're going to do the right thing. >> it's very difficult. in eastern iraq, the u.s. has some ground presence in the form of advisers. there are probably intelligence officers, things like that. you can collect a lot of intelligence with assets like drones. so there can be some going to be the boots on the ground that take the territory that air strikes sort of open up opportunity to seize. >> sreenivasan: that record has been mixed at best when it comes to iraqi forces staying through the fight. >> absolutely. the iraqi security forces in particular are very mixed. their special operations units are quite effective and have fought very well within the limitations that they have. but there's only a few thousand of them. the vast bulk of the iraqi military suffers from a lot of weaknesses, and the kurdish poosh, who have fought better have their own weaknesses as well. there are real questions about who will be the effective boots on the ground. >> sreenivasan: isil, isis, islamic state still control major cities. how do you from the air try to clear some of those cities when these guys can go right back into the civilian population? >> it's very challenging. even with the united states having tens of thousands of troops in iraq and at the highest sirnlg, we weren't able to completely eliminate al qaeda in iraq, which was sort of the predecessor of the islamic state, and they hung on and had a presence in mosul, sort of throughout the entire time the u.s. was there, even if it was a much lower level presence. it's very challenging to clear that kind of presence out. >> sreenivasan: one of the longer term concerns is the training we would provide or especially the equipment we would floyd this fight. sometimes the equipment is used against us. there's a backlash when it falls spot wrong hands. how do we protect against that? >> it's extremely challenging. people talk about training of the iraqi security forces. we had a big endeavor to do that for years in the iraq, and, yet, you saw collapse in mosul and the seizure of a lot of equipment. the key is to build up the capabilities of the organization before you just dump a lot of weapons on it, and that's also, i think, a risk across the border in syria, with trying to arm syrian rebels is you have the the possibility that without building up the organization, dump weapons on them, the islamic state can then just take them from them. >> sreenivasan: speaking of syria, when you go across that border, who is left to be the ally there? it seems they've been, on the one hard, decraided by alba shar's forces and on the other hand degraded by isil. >> there's a fragmented selection of militias there that will have to be rebuild into something that resemblesoon army. whatever the challenges in iraq are, in terms of providing support to potential local ground forces, i think the challenge is much greater in syria. >> let's talk about timelines. the president said let's brace ourselves for a long-term engagement. how long is this going to take? >> it's going to take a very long time. i think years would be pretty generous. now, years would be to completely defeat the group. i think you can make real progress in taking some of the key cities back on a shoart timeline but it's still not going to be days or weeks. it's probably going to be months or years. >> sreenivasan: and that's in both iraq and syria? >> i think syria is probably more challenging. the islamic state is much stronger than most of the rebel troops there, rebuilding them into something like a functioning army i think will take a very long time. you can launch strikes in syria without rebuilding those forces, but then you're, at least indirectly, about the to benefit president assad's regime. >> sreenivasan: austin long, thank you very much. >> thank you very having me. >> sreenivasan: and now to our signature segment. tonight, part two of a series by the center for investigative reporting. the focus: china's purchase last september of america's largest pork producer, smithfield foods. last night's report examined the chinese government's role in the $4.7 billion acquisition. tonight, a look at how the deal fits into the chinese government's plans to feed its 1.4 billion people. the story, by nathan halverson, begins in henan province, the "breadbasket of china." >> reporter: li grows crops on a few acres of land about 300 miles south of beijing. farmers like li produce the bulk of china's food. >> ( translated ): it has been the same way-- wheat in the spring and corn in the fall. always this way. it has never changed. ( laughs ) >> reporter: but change is coming. farmers like li can no longer produce enough food to satisfy china's growing demand. the country is in the midst of the largest agrarian reforms in world history. >> china is roughly the same size as the united states. the cropland area is similar. the grain harvest is similar. the difference is, in the u.s., we have 300 million people, and there they have 1.4 billion people. >> reporter: lester brown is a food economist and author of "who will feed china?" he says china must now make the most of its limited farmland. >> and they're feeling very vulnerable at this point. they know that they can't feed themselves anymore. >> reporter: that fear has rattled the chinese government. in 2011, it announced a five- year plan to radically overhaul china's farm system and relocate 250 million farmers to cities. >> keep in mind that most of the leaders in beijing today, at can remember the great famine in 1959-61 when 37 million people starved to death. >> reporter: today, the government is no longer worried about starvation, but satisfying an affluent and growing middle class that wants to eat like americans. the government needs to keep people happy, says the former head of goldman sachs in china, fred hu, now an advisor to the chinese government. >> the political system we have in china, we have a one-party and the party, the legitimacy depends on its ability to deliver economic prosperity and consumer satisfaction, if you will. >> reporter: hu, a chinese citizen, says that what consumers want to eat, increasingly, is meat. and meat is so resource- intensive, it puts even more pressure on china's strained farms. >> it seems highly unlikely for china to be self-sufficient, so china will have to import a large quantity of foods from all over the world. >> reporter: last year's takeover of smithfield foods, the largest-ever chinese acquisition of an american company, was a significant part of the government's effort to acquire resources from outside its borders. smithfield c.e.o. larry pope is now an executive with the chinese firm. china consumes 50% of the world's pork? >> half of all the world's pork is eaten in that one country and growing, and growing steadily every two or three years. china's consumption demand grows by the whole size of the u.s. market. >> reporter: pope says smithfield is already gearing up to ship more pork to china. >> in many respects, this is carrying out the government's five-year plan, which is to improve the quality and the security of their food supply. >> reporter: chinese consumers view american brands, like smithfield pork, as safer than domestic products. after years of food scandals, they have become wary of chinese brands. >> the last couple of years, there has been a string of food safety accidents-- baby powder formula or meat products-- so that has caused a big scare and concern among chinese consumers. >> reporter: officials are now taking a closer look at where the food is coming from. >> ( translated ): my name is wang. i'm a pig farmer. >> reporter: wang is a typical hog farmer, raising about 100 pigs in a barn attached to his house. 200 million small farmers scattered across the countryside raise most of china's livestock. the government knows food safety isn't always a priority on these farms. >> ( translated ): raising pigs is actually easy. they can eat whenever they want. you just throw the food in the pen. when they're hungry, they will come to eat. if not, whatever. >> reporter: i noticed some open vials on a dirty table. some farmers have been caught using illegal growth hormones. i asked wang about the vials. >> ( translated ): a while ago, the pigs got sick and were coughing. >> reporter: keeping tainted pork off chinese plates has been a struggle in china's fragmented farming system. scott rozelle is an agricultural economist at stanford. >> you have all these hogs coming from everywhere. they have foot and mouth disease. they could have other pork diseases. you may have been giving the injections of hormones to make them grow faster, and you don't know what you're getting. and so, there's absolutely no way you can retrace any food safety from there. >> reporter: modern facilities provide an easier way to monitor food safety, a key goal of the government's five-year plan. china is pushing to replace family farms with large-scale operators like shuanghui, the company that bought smithfield foods. we received a tour of a shuanghui plant from its president, zhang taixi. >> ( translated ): the current technologies of this factory are a little outdated. the new factories we are building will be state-of-the- art. >> reporter: with the takeover, china's largest meat processor acquired smithfield's food safety technology. zhang told us the government is rapidly overhauling china's meat industry, closing half of its slaughterhouses in the next year. >> ( translated ): the number of slaughterhouses will be reduced from 20,000 to 10,000 by 2015 in order to meet the standards of food safety as well as environment protection. >> reporter: the rapid increase in meat production has resulted in devastating environmental damage, another issue rattling the chinese government. it estimates that three-quarters of its waterways are polluted, and nearly half of that pollution comes from agriculture. here in china, small pig farms still account for about 70% of production. each farm will have maybe about 100 pigs, each pig producing ten pounds of manure every day. the downside of these operations are that the manure has nowhere to go except for in the local culverts like this. all the agricultural waste makes its way down china's rivers, into its lakes and out into the ocean, leading to widespread and toxic algae blooms, affecting fisherman like jin tao. >> ( translated ): it's got algae. a lot of the water has algae. it's scary. if you drink the water, you will get sick. >> reporter: shuanghui hopes that smithfield's modern waste management technology will help tackle pollution. shuanghui says it is committed to building more environmentally friendly facilities like the one behind me, where the 28,000 head of hogs that are raised every year have their manure running off into the lagoons, capturing it and preventing it from going into the nearby river. how china deals with all these issues-- from food shortages to the environment-- will have a global impact. the smithfield purchase included hog farms in poland, mexico and the united states. >> over the long term, more hogs will be produced in america, but that would be more hogs produced in order to ship pork to china. >> reporter: patrick woodall is the research director at food and water watch, an environmental advocacy group. >> they get the meat; we get the manure. we export the best part of what rural america has to offer, and we keep the waste. >> reporter: protecting the environment is one of the challenges facing the u.s. as it supplies food to china. >> no other country has ever had a billion people moving up the food chain consuming more livestock products, grain- intensive livestock products. >> reporter: in addition to shipping more meat to china, american farmers are sending it more livestock feed than ever. two years ago, china became the largest importer of u.s. farm products. >> when you're driving through the country right now and you see these big fields out there, one out of four rows goes to china. so, this is a huge market, and it's a market that i think is going to get even bigger because their middle class hasn't stopped growing. >> reporter: feeding china's middle class, which is now larger than the population of the u.s., is a growing challenge for the entire world. >> sreenivasan: who's behind the chinese takeover of the world's largest pork producer? watch part one of the center for investigative reporting's series, "food for nine billion." visit newshour.pbs.org. the department of homeland security is contemplating the most significant restructuring since it was created after the september 11th attacks, in order to better secure the border with mexico. devlin barrett of the "wall street journal" wrote about it on thursday, and he joins us now from washington. what's at stake here in the recent crisis, if you will, of a birch of young migrants crossing the border sheds some light on the fact that there are at least two big agencies, the customs and border protection folks, and the immigration and customs enforcement folks, all tackling this. >> right. and what it speaks to is there are really two forces at play here. one is the immediate crise of all the children crossing, and they're starting to see some improvement, some reduction in the numbers there. but there's the broader issue of what pretty much both sides agree is a kind of broken immigration system in this country, and the border is part of that. and so you have these two forces, but the long-term structural problems that people feel exist, and the short-term, immediate problem of so many children cross the border, and they're both pushing the department of homeland security to consider some pretty significant changes in how they're organized and how they police that border. >> sreenivasan: so how would it change? >> well, what they're talking about doing is creating a southern command, essentially, taking a military modelle of leadership and structure and combining these two agencies operationally for a lot of law enforcement work so that you essentially have a more streamlined chain of command, and you have more coordination between these two groups of people who both have a big part in this, but don't always work in the same room together. >> sreenivasan: if you didn't merge the two agency, wouldn't you have two chains of command and essentially codify the turf palts? >> right, well, that is the concern, one of the concerns expressed by some of the information i talked to, sucreate this military-style chain of command, you could end up with two reporting chains, two sets of bosses, essentially, and how will that work? now people who think this is a good idea say, look the military has shown you can do that and do that effectively and efficiently. there is, obviously, some skepticism in some quarters. the one thing people do say is they have a manpower-- there's a constant manpower challenge on the border. and this is one of the ways they are considering one of the things they have on the drawing board as they try to come up with ways to address that manpower issue. >> sreenivasan: are there significant inefficiencies now where the agencies aren't working together as best they could? >> you know, there's a bit of disagreement about that. what this is really about is the notion of policing the border and going after sort of the large smuggling organizations, both human smuggling and drug smuggling. some people believe if you actually got these guys doing more joint operations together, like the military often does in its southern command structure, that you will actually do bigger cases, get better results. you know, there are skeptics who say we are already doing this work, you know, moving the chairs around, creating a new title doesn't necessarily fix, you know, the challenges we have. >> sreenivasan: this is on the drawing board phase now. how long before something like this could get implemented, proposed to congress, work its way through? >> you know, it's a tricky thing. they're talking to congress in little bits and pieces about this. it sounds as if no one's really going to try and put anythinged for before the election. i think that's probably just too difficult. and i think, frankly, people want to see what the election results are, and if that poants away towards some sort of agreement as to some things you could do on border security. politically, the republicans have been arguing for a while you shouldn't do any major immigration reform without doing border security first. this could become a piece of that discussion, but i would be surprised if that discussion happens before the election. >> sreenivasan: all right, devlin barrett from the "wall street journal" joining us from washington, thank you very much. >> thank you. >> sreenivasan: how do you move one of north america's largest works by pablo picasso? the answer, of course, is very carefully. last weekend, here in new york city, the newshour's stephen fee watched as a crew worked overnight to remove and then move a delicate stage curtain painted by the spanish artist in 1919. >> reporter: the nearly century-old tapestry depicts resting bull fight spectators and for 55 years adornd the walls of one of the new york city's most iconic park avenue lunch spots. and this september, after more than 12 hours of careful maneuvering, workers removed the final staples and screws holding the 19 sp 20 foot curtain to the wall of the four seasons restaurant. >> i was really concerned by the time we got to the top it might tear. and i've had many sleepless nights thinking of this curtain. >> reporter: throughout the night, workers rolled the curtain from bottom to top, using a 23-foot-long tube, then lowered it to a steel rig, affording upside down views of two bull fight fans. last fall, the building owners decided to move the canvas curtain, saying they needed to repair the wall behind it. but the curtain belongs to the new york landmarks conservancy. it was donated to the group by the building's former owner, and the conservancy sued to keep the work in place. the parties settled this june, with the building agreeing to front moving costs and new york historical society agreeing to display the work permanently. >> by going to the historical society, it will continue to be new york's picasso, and thanks to all the fighting, it's now new york's best-known picasso. >> reporter: the tapestry emerged unscathed, shrouded in bubble wrap. it now heads to massachusetts for a bit of cleaning. the new york historical society hopes to raise the curtain once more next summer. >> sreenivasan: some more news before we leave you tonight. the u.s. state department has issued an emergency message warning of possible imminent terror attack in uganda by al-shabaab. it instructed americans there to say home. secretary of state john kerry says iran has no role to play in the coalition being formed to wage war on islamic state fighters in iraq and syria. and in case you missed it last night, astronomers say vivid northern lights might be visible in the sky across the northern united states again tonight. thanks for joining us. i'm hari sreenivasan. see you tomorrow night. captioning sponsored by wnet captioned by media access group at wgbh access.wgbh.org >> pbs newshour weekend is made possible by: corporate funding is provided by mutual of america-- designing customized individual and group retirement products. that's why we are your retirement company. additional support is provided by: and by the corporation for public broadcasting and by contributions to your pbs station from viewers like you. thank you. the following... one of the jobs of legal services lawyers is to challenge illegal laws and to challenge illegal administrative decisions that adversely affect the poor, to try to bring about some change for the poor people that really means something. luis valdez: the year is 1969. cruz reynoso heads one of the nation's best antipoverty programs. reynoso is in a tight spot. on one side, his old friend césar chávez demands