captioned by closed captioning services inc. tonight, the special edition of "world news." helicopter down, the tragedy in afghanistan. 30 american troops killed when a nato helicopter is shot down. 22 of them, navy s.e.a.l.s just weeks after their comrades killed osama bin laden. president obama tonight calling it a reminder of the extraordinary sacrifice of america's military, and we go inside the world of the s.e.a.l.s, their survival skills, their extraordinary training and, most of all, their mind. and the other major story tonight, america's credit. this historic downgrade, the u.s. losing its stellar credit rating. what it could mean as soon as monday for your credit card, your mortgage and the future of american jobs. team coverage on the credit crisis and the helicopter down tragedy in afghanistan starts now.

and good evening. we begin tonight with that headline out of afghanistan that stunned and saddened so many of us today when we heard it. what is now the single deadliest day for u.s. forces in that war. a military chinook helicopter was shot down in the dark of night killing 30 u.s. troops and 8 afghans, everyone on board. abc news was the first to report that among the dead, 22 navy s.e.a.l.s later learning most of them were from team 6, the elite of the let. fellow members of their team were the ones that killed osama bin laden. tonight our team from washington to afghanistan reporting in here, and we begin with abc's martha raddatz. >> reporter: it is a crushing loss, the most elite forces in the u.s. military, 22 s.e.a.l.s killed in the fiery crash of their chinook helicopter along with air force and army personnel. 30 americans in all. 8 afghans and a dog trained

specifically for special opopations. it happened last night near a taliban stronghold in wardak province. u.s. forces were engaged in a firefight on the ground. the chinook full of s.e.a.l.s was on its way to help when it was shot down probably by a rocket-propelled grenade. an eyewitness describes the same. "we were outside our rooms on the veranda," the witness said, "and we saw this helicopter flying very low, and it was hit by a rocket, and it was on fire. it smarted coming down, and it crashed just yards away from our house close to the river." most of the 22 s.e.a.l.s were part of s.e.a.l. team 6, that heroic uninithat carried out the highly successful raid on osama bin laden's compound in may, but none of those who actually took part in the raid are believed to have been on this helicopter. president obama in the midst of an economic crisis received the terrible word last night.

u.s. special operations teams carry out up to a dozen missions a day in afghanistan. 3,000 to 4,000 last year alone. since 9/11, there have been 32 s.e.a.l.s killed, but 22 in 1 day is devastating. there are just 300 men in s.e.a.l. team 6, so in this one incident, more than 7% of the highly trained, highly valuable s.e.a.l. team 6 has perished. >> it's a terrible loss, a terrible human tragedy, but it's also a significant strategic loss for the nation, as well. it takes a generation to grow a special operations warrior. >> reporter: a loss for the nation and a loss for a tiny and close community that one officer said has done more for this nation than we will ever know. >> and i'm joined by martha raddatz in washington. so much loss today, martha. and we know that these s.e.a.l.s

operate in such secrecy and understandably so. how does the pentagon go about notifying the families and in doing so protecting the privacy even now? >> reporter: well, i'm sure they had notification teams out all night. i've been thinking a lot about that, david. 22 notification teams in just that small s.e.a.l. community, eight more elsewhere in the nation. that's just so many, and what makes this even more tragic is that it follows on the heels of that bin laden raid where those s.e.a.l. families, t t s.e.a.l.s themselves in the entire country felt such pride but tonight, as you know, is feeling such pain. >> martha raddatz in washington, martha, thank you. mike boettcher has embedded with u.s. troops so many times in afghanistan for us, and he is there on the ground with reaction there, mike. >> reporter: david, i'm speaking to you from forward operating base in the kunar province in northeast afghanistan.n. soldiers of the 25th infantry division's task force cacti are based here, and they often go out on these night operations so the news of this crash has hit them hard. every time they go out, they

know they have death tugging at their sleeves. the taliban have become more adept at using rocket-propelled grenades to shoot at the chinook. my son carlos and i have been out on several of these missions where you're in concealed locations, very difficult, flying over mountains where you can be shot at and when you land you're surrounded by the taliban and there's usually a big fight, but they keep on going even though the trtrp withdrawal process has begun in this area, as well. david? >> mike boettcher inin afghanistan. mike, thanks. i want to bring in christiane amanpour, the anchor of abc's "this week." and, christiane, as we heard martha report there at the top of that phone call, the president received last night on this, you learned the briefings continue today, and the president issuing a statement. >> that's right, the white house says the president was, of

course, briefed several times, and then he did issue a statement and, of course, he said that he and all americans mourn the loss of these american service members. he sent out his sympathies to the families of those who were killed and to their loved ones and he talked about how it reminds everyone of the sacrifice that these people are making for afghanistan and for a free a a more peaceful afghanistan, and he included in his remarks a remembrance of the afghans who also died alongside the americans in that terrible attack. >> and, christiane, in the bigger picture here, what does this mean for the state of play in afghanistan? >> well, david, you know, there have been attempts to paint sort of hopeful and positive messages about what's happening in afghanistan. you know the president is withdrawing some of the search forces, and we've seen those, that evidence on the ground is very worrying. over the last several weeks a spate of assassinations of pro-american afghan officials working in kandahar, and now we see these attacks on helicopters in this, the single deadliest in that more than ten-year war now, and so there are deep concerns about what's going on there right now. >> all right. christiane, we'll be watching "this week" first thing in the morning. in the meantime, tonight to the training, the unrivaled discipline of the navy s.e.a.l.s, their skills unmatched and so are their

minds. here's abc's chris cuomo now. >> reporter: designed to be the best anywhere doing anything, whether sea, air or land, that's what s.e.a.l. stands for. >> it's a self-contained unit that can go anyplace in the world and literally do nothing but kick ass. >> reporter: a superhero has nothing on these guys. recruits are trained to swim 350 feet underwater with their hands and feet bound. they're taught to survive in arctic conditions, even submerging in freezing water. they also have to endure exposure to tear gas. only men ranging in age from 26 to 33 try out to become 1 of the 2,500 s.e.a.l.s. training takes two years. 75% don't make it through. even if they do, they need years more experience in the field to even be considered for the elite squad team 6. >> by the time you get to 6, you're either going to overcome any weak points that you have in any of those disciplines or

you're going to wash out and say you're a good s.e.a.l. but you're not good enough for this. >> reporter: and richard marcinko would know. he started team 6 in 1980. on missions they may jump from a plane 11 miles up, sit in deadly silence trained to camouflage themselves to any environment or hold their breath underwater for over two minutes without releasing a single bubble, and, of course, they can shoot with pinpoint precision. for example, they rescued sailors from "the alabama maersk" taking out pirates through an open window on a rocking ship from 120 feet away in the dark. >> when you're doing hostage rescue, so you're trained in a 3x5 with a forehead for the brain matter or the heart. >> reporter: what marcinko says really sets a s.e.a.l. apart, their most deadly weapon is their mind. >> body is only tissue. the brain controls it, and the brain will push them beyond what you and i and normal people think the body can take. >> reporter: chris cuomo, abc news, new york. >> our thanks to chris, and

that's our coverage of the tragedy in afghanistan this evening. we do move forward here and to the economy and the reporting on bringing america back. the push for ideas and solutions in this country and this evening here, one of the biggest challenges yet. for the first time in nearly a century, the u.s. no longer has a aaa credit rating. the wall street firm standard & poor's has taken the unprecedented step of loweweng america's credit rating one notch. but this is a seismic shift that could affect everything from your mortgage to your credit card and as early as monday morning. we'll have more on that in a moment, but first this decision to downgrade and why. here's abc's david kerley in washington. >eporter: standard & poor's is making no apologies tonight for downgrading america, telling investors the gold standard of global finance is no longer the safest place to put your money. >> our job is to hold the mirror up to nature, and what we're telling investors is that the united states government is slightly less creditworthy. >> reporter: the rating agency says, in essence, washington is broken.

>> put something on the table. tell us where you are! >> reporter: and hasn't done enough to cut t e debt pointing to the gulf between the political parties, which used the debt ceiling as a bargaining chip leaving the u.s. less stable, less effective. >> this is not really a serious way to run the country. >> reporter: the obama administration fought back against the downgrade pointing out that the rating agency made a $2 trillion mistake in its math declaring "a judgment flawed by a $2 trillion error speaks for itself." the entire financial world will be holding its breath tomorrow as asian markets open. treasury officials wililbe manning their markets room watching to see the effect on stocks and bonds and the retirement accounts of millions of americans. >> even if it's not great on monday and the market trades down, i don't think we're going to see significant trading down in terms of u.s. treasasies. there is nowhere for the rest of the world to go. america still remains the best place to put your money. >> reporter: the other two rating agencies still consider the u.s. aaa.

but for standard & poor's, the united states credit is now rated lower than france, canada, norway and the isle of man. >> absolutely have a point. we are definitely in a less good place than we have been in previous years, previous decades. >> and so david kerley joins us now from the white house. david, we mow that the president's being briefed today on afghanistan, but also the economy, a a is there any chance we'll hear from the president to influence global markets before they open? >> reporter: you know, we know that the president did talk to some experts today up at camp david. he did not come back to washington. not expected back until tomorrow, david, and we have not had any official word from the white house, but as you remember, even during the debt negotiations when certain deadlines were reached, the president tried to reach out to the financial communities before those asian markets opened, so i wouldn't be surprised if we hear from him tomorrow afternoon, david. >> all right. david kerley at the white house tonight on a very tough weekend for this country. i want to bring in abc's bianna golodryga who follows the markets for us. we heard david say so much attention on the global markets, on wall street first thing monday morning, but you were telling me earlier in the

newsroom that there's going to even be more focus on a possible other shoe to drop. >> that's right. we know that the downgrade will have some effect on borrowing costs. how much, we don't know. we're in unchartered territory here. we have that cushion a bit because the other rating agencies didn't downgrade. what i'm told to pay attention to is the banks. if u.s. banks are downgraded we could see a rise in borrowing rates. >> credit card rates and mortgages. you were looking at the average american home, $200,000 or so. if this goes up just a half a point, the interest rate, how much would that affect the length of, say, a 30-year mortgage? >> yeah, even if mortgage rates go up by half a percentage point, an average 30-year mortgage could see costs, total costs go up by $19,000, again for an average u.s. home roughly $200,000, so you see the ripple effects there for the major part of the country and everything from car loans to credit card loans to small business loans, so all eyes will be on what happens next and particularly what happens monday on wall street. >> all right. stakes very high. bianna golodryga tonight, thanks so much. and there is one more note on the downgrade.

a blistering reaction by china, the largest foreigner holder of debt. china says the u.s. must "cure its addiction to debts and live within its means." china is calling for cuts to america's, quote, gigantic military expenditure and bloated social welfare programs." by the way, china's credit rating is still lower than america's. we do move next to a remarkable scene in texas today. a giant prayer for this country with m my asking, was this gathering of thousands an unofficial campaign kickoff? texas governor rick perry led the prayer, and many believe it could very well lead someplace else, the campaign trail. here's aaron katersky. >> and glory to jesus. >> reporter: it had the look and feel o oan old-fashioned revival. >> spare your people, lord. >> reporter: texas governor rick perry quoted scripture and led 30,000 christians in prayer. >> as a nation, we have forgotten who made us. >> reporter: the likely presidential candidate appealed to a higher power. >> his agenda is not a political agenda.

his agenda is a salvation agenda. >> reporter: to address the politics of the day. marketplace.ar in the we see anger in the halls of government.. >> reporter: perry commanded this stage as he ponders the national one. >> governor rick perry is like a king over this land. >> reporter: but perry's open mix of faith and politics risks alienating even soso christian voters. >> my simple message to him is, don't mess with the constitution. >> reporter: the sponsor of perry's rally, the american family association, opposes homosexuality, women's rights and religious diversity. >> rick perry is going to have to answer some questions about the people there that he's on stage with at this event. >> reporter: perry claims his tent is open to all. >> he's a wise, wise god, and he's wise enough not to be affiliated with any political party. >> reporter: but it's perry's affiliation with today's event that could hurt his broader appeal. aaron katersky, abc news, new york.

and still much more ahead here on "world news" this saturday night. those electric cars about to hit the road. they do save on gas, but there is something hidden, and even why we had to listen very closely. and then later here, a giant day for anyone who ever loved lucy. tonight the answer to that question, which was lucy's favorite episode? you could save a bundle with geico's multi-policy discount. geico, saving people money on ore than just car insurance. ♪ geico, saving people money on moe than just car insurance. that's how it is with alzheimer's disease.

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helps defends against occasional constipation, diarrhea, gas and bloating. with three strains of good bacteria to help balance your colon. you had me at "probiotic." [ female announcer ] phillips' colon health. we have reported so much on electric cars asking whether the gas savings really makes them a viable alternative in the economy, and it turns out they not only save on gas, they save on sound, and they are nearly silent, but the question now could that be dangerous? and here's abc's david wright. >> reporter: that gas-guzzling internal combustion engine is what gives the car its signature sound. the car of the future sounds like -- nothing. >> silence is one of the selling points for these cars, but there's quiet, and there's too quiet. with these new electric vehicles, the power windows are louder than the engine. you don't even hear it coming

and research has shown that electric vehicles are twice as likely to hit a pedestrian. it's a real problem for blind people who rely on their hearing to know when to walk. so the designers of the new nissan leaf brought in a ringer. the hollywood sound designer from "the fast and the furious." they wanted it to sound fast and furious? >> they wanted hollywood's input, i think. >> reporter: peter brown knew just what was missing. he approached it just like a movie. took a video, stripped out the sound then added new sounds of his own. >> you've got electric razor. gyroscope, heartbeat, spaceship. the fascinating thing to me isis that it really doesn't need to sound like a car. it could sound like those little spaceships in "the jetsons" cartoons. [ playing the theme to "the jetsons" ] >> reporter: which is kind of what nissan wanted.

>> i can easily imagine a day when you can change the sound in your car as easily as you change the ring tone on your phphe. >> reporter: the result, certainly makes the leaf distinctive, but is it more visibleleo blind people? we drove it past our panel of experts. how would you know that's a car with that high-pitched kind of squeaky sound? >> i didn't realize that was the car until like i said it was right in front of me. >> reporter: nissan may still have some work to do. david wright, abc news, los angeles. and when we come back in the broadcast tonight, celebrating "i love lucy." which was your favorite episode and more importantly, which was hers?

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she was a beauty and a star of radio and movies long before that brand-new thing called television. lucy and husband desi arnaz had an idea, what would famously become the "i love lucy show." it instantly became a hit in america, the first television sitcom to do so. who could forget those moments? the chocolate factory. >> speed it up. >> reporter: the vegamin. >> are you unpoopular? well, are you? >> reporter: the baby. >> ricky, this is it. >> this is it. >> this is it! >> this is it. >> let's go. >> let's get going. >> call the doctor. >> call the doctor. >> reporter: lucy was a character so many at the time could relate to, a housewife who was the real driver in the family. >> is this going to be the one about how i'm a wife and mother and my place is in the home? >> reporter: and behind the scenes she was a pioneer, the first woman ever to run a major

tv studio, desilu studios, and "i love lucy" she never thought would run for nearly a decade and rerun even today in more than 70 countries around the world. >> i expected only to do the show for a year and then have some like home movies to show the baby that i had just had. >> reporter: and that question what was her favorite episode? she revealed it to an audience once during a commercial break. it was the grapes, the stomping that still has us laughing today. a laugh or two on a day when we sure needed it. we'll check in with martha raddatz on our top story, a closing thought, a hopeful one from martha in just a moment. t called atrial fibrillation, or afib, that's not caused by a heart valve problem. today we have pradaxa to reduce the risk of a stroke cacaed by a clot. in a clinical trial, pradaxa 150 mg reduced stroke risk 35% more than warfarin.

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with ginkgo to support memory and concentration. plus it supports heart health. [ bat cracks ] that's a hit. one a day men's. as we reported here at the top, it was the deadliest day of the war in afghanistan, 30 amamican, 22 navy s.e.a.l.s lost, and, martha, i know you traveled to afghanistan so many times and you know the scope of this loss. >> reporter: i do, david. they are truly amazing human

beings. they are also husbands, fathers, but they are also modest. that's the word that sticks out to me. last week i had the pleasure of interviewing admiral eric olson. he heads the special operations forces. he's very modest. he had a big part in the osama bin laden raid, and this is what he said about that. obviously you're pleased, but i think anybody who has been in this business this long is conditioned to think that the very next thing could go wrong. that is so true, but let me also end on this note, david, another officer i spoke to today, and you've heard this so many times in war, said, they died doing what they loved, and i know that's true. >> what they loved. martha raddatz, our thanks to you tonight. that is the broadcast. more on "gma" and on "this week" first thing in the morning. i'll see you back here tomorrow night. good night.

>> alan: good evening. 30 american troops killed in afghanistan. the deadly is single loss since the war began. many killed were part of the tight-knit navy seal team. it happened in afghanistan after insurgents shot down the helicopter. >> this is the greatest single loss of american force since the war in afghanistan began in 2001. naval officials say it's a tragic loss of an elite group of seals on a mission to support troops pinned down by insurgents. the nato chinook helicopter like this one was on a mission when it went down. everyone onboard was killed. the dead include more than 20 navy seals of seal team six. seven afghan troops, an