It's hard to quantify progress in Afghanistan, but all too easy to measure the cost in lives. This is already on track to be the deadliest year for American troops, and now a desperate search is underway for two U.S. sailors who have gone missing and may have been captured. The Taliban are making some claims about their status, but the military isn't confirming them. Meantime, on a visit to Afghanistan today, Admiral Mike Mullen, the chairman of the Joint Chiefs of Staff, warned the U.S. will continue to suffer casualties and face tough resistance, but that "slow and steady" progress is being made, and that he still thinks the momentum of the insurgency can be reversed. NBC News Pentagon Correspondent Jim Miklaszewski will join me tonight to tell us more about the circumstances surrounding the disappearance of the servicemen and this latest juncture in the 9-year-long war.

There is also news tonight about Tony Hayward, the embattled BP CEO who once famously uttered the words "I'd like my life back" as oil poured into the Gulf. Well, now it appears that story may have come full circle. We'll report that tonight, as well as what's going on back at the oil well site now that the storm threat has passed.

Many of us are crying "uncle" when it comes to this heat wave, so we'll look at the national forecast on tonight's broadcast, as well as how this weather has put a number of Americans in danger.

I hope you can join us for NBC Nightly News.

BP's reluctance to declare the capping operation a success is understandable, especially when you look at the string of failed fixes and low-ball oil flow estimates from the early weeks of this disaster. Anybody remember "top kill?” After 3 months of this environmental horror show we're all anxious to hear the words, "we have killed the well." But we're not there yet. The experts keep telling us much can still go wrong. Even if the capping turns out to be an unqualified success, they've got to complete the relief wells in order to close it off for good – and that too is not a sure thing.

On tonight's broadcast we will look at the factors behind the "cautious optimism" being expressed by the folks in charge of the operation and the unknowns that are still keeping them awake at night.

In the meantime the rest of us -- especially those who live and make their livings along the Gulf -- can only look at the underwater video and take comfort in the fact that at least for now there is no oil escaping into the sea. Tonight we'll also hear from some of those residents, and look at the cleanup challenge ahead.

I hope you're having a good Sunday. We'll look for you later on NBC Nightly News.

I can't recall exactly when I read "To Kill a Mockingbird." I do recall that as for many of you, it was required reading at some point in my education. I also remember its raw and layered portrait of the Jim Crow era South – told through the voice of a child – resonated with me for a long time. Harper Lee's Pulitzer Prize-winning work turns 50 this weekend. Unfortunately I have forgotten some of the key plot twists, and thought this might be a good time to re-read this American classic. But I have to admit I was a little surprised to find Amazon.com customers gave it only 4 out of 5 stars. Certainly a good rating, but I guess not what I expected for a cherished literary piece. I'll read it again and judge for myself. In the meantime, we'll take a few minutes on tonight's broadcast to look back on "To Kill a Mockingbird," and examine why it endures – 4 stars not withstanding – as a must-read for so many Americans.

Also, NBC News science and environmental expert Jeff Corwin is going to join us live from the Gulf to show us how scientists are desperately trying to save already endangered sea turtles from the ravages of the oil slicks now covering their habitat. We'll also have more encouraging reports coming from BP on progress being made on two fronts to both contain the leak and plug the well.

I hope you'll join us tonight for NBC Nightly News.

The video feed from below the Gulf of Mexico is even more sickening to watch today. The oil is now flowing unchecked into the water after robots removed the containment cap that was helping to capture some of the escaping oil. It could flow like that for a couple more days. Okay, that's the glass half empty assessment. Now for the glass half full. By removing the cap, BP engineers will now position a new, better fitting cap that -- if all goes perfect -- could effectively contain the leak by early in the week. There are plenty of ifs and wiggle room built into the timetable of this operation, but it's hard not to get the feeling that the end game, as far as stopping the flow, could be in sight. Our Anne Thompson, who has been on this story from the beginning, will tell us what the game plan is, and update us on where it stands.

We'll see you later for NBC Nightly News.

I hope you're having a good Independence Day weekend. No rest for the weary in the Gulf of Mexico of course, but just might be something to celebrate. BP's new executive in charge of the oil response says the relief well, meant to cap the oil leak, could be finished sometime this month, ahead of schedule. That declaration included a lot of "ifs" about the weather cooperating and other variables. Given their track record, it's understandable that up until now BP has been trying to under-promise progress, predicting they'd finish the relief well in August. NBC's correspondent Thanh Truong has been out with the Coast Guard today and will have a better read for us on where things stand on our broadcast tonight. Kerry Sanders is also going to give us some insight into how those undersea robots tending to the well are actually operated. It's delicate work, especially given they're operating 5,000 feet under the surface and their operators are in Houston.

As many of us find time to celebrate and enjoy some time off this holiday let's remember all the hard working folks on beaches, ships, and seaborne platforms who will be pushing straight through the weekend trying to stop and contain the damage from this horrible scourge.

In the meantime we'll look for you tonight for NBC Nightly News.

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Veteran New Orleans journalist Garland Robinette from WWL radio will be joining us again on the broadcast tonight to lend his perspective on "the continuing nightmare" that is the Gulf oil spill crisis.

On May 13, Garland spoke to us about the increasing anger and despair locals were already experiencing two weeks ago.

You can watch that clip here:

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Mos Def, Lenny Kravitz, the Preservation Hall Band, Trombone Shorty, and Tim Robbins teamed up recently to record "It Ain't My Fault," to benefit Gulf Aid. Check out the video below: