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.