SCIUTTO (voice-over): From the air, the scale of the disaster is alarming, rivers swollen miles beyond their banks, behind them, a trail of destruction.
(UNKNOWN): I've never seen such a large area receive as much damage as I have seen in Swat.
SCIUTTO: Flying into the hard-hit Swat Valley aboard U.S. Army relief helicopters, we saw every single bridge destroyed, and on the ground, villages now dependent on aid from the air.
In Bahrain, population 40,000, its once waterfront hotels now in the water. It has no power, no clean water, and no roads in or out.
(on-screen): So it's cut on both sides?
(UNKNOWN): Yes, it's gone on both sides.
SCIUTTO: So this is -- this is an island now?
(UNKNOWN): (OFF-MIKE) is an island.
SCIUTTO: These American helicopters are ferrying supplies from bases like this one to villages that are completely cut off. We're seeing rice and flour and other supplies going in. The helicopters are today their only lifeline.
(voice-over): Food, much of it from the U.S., in, refugees out. For the fight crews diverted to relief from combat in Afghanistan, it is a dramatic shift.
(UNKNOWN): I sat down and spoke to all the troops about turning that switch off. But the first time I looked at those children needing help, I was no longer concerned.
SCIUTTO: U.S. and Pakistani relief teams are fighting against the clock. This weekend, the first confirmed cases of cholera, a potentially deadly disease that's the result of the lack of clean drinking water.
For many Pakistanis, the flooding and its aftermath is a gritty reminder of all the ways the government has failed them, a plodding response, a state budget dependent on fallen loans, shoddy infrastructure. Seeking to take advantage of the chaos, the Taliban is delivering help where the government is not, particularly in Swat, which saw the end of a massive anti-militant offensive just weeks ago.
For the U.S., however, one sign of hope. America is deeply unpopular here, but the relief effort is winning hearts and minds. Among them, the mayor of Bahrain, who told me the U.S. is outdoing Pakistan's Muslim allies.
(UNKNOWN): And in this disaster, the Islamic countries give their aid after America.
SCIUTTO (on-screen): Does that surprise you?
(UNKNOWN): Yes, surprise, surprise.
SCIUTTO: A good surprise?
(UNKNOWN): Good surprise, yes.
SCIUTTO: The first priority of the American relief effort is to help the millions in need, but U.S. officials will say very openly it's also intended to improve America's dismal image here. Sixty-eight percent of Pakistanis view the U.S. negatively, and the sight of those American helicopters a very tangible form of outreach.
And, Christiane, on a lot of that food going in, we've seen them labeled very prominently with American flags.
AMANPOUR: Jim, indeed. Let's just talk a little bit more about that, because you mentioned the disapproval rate because of the drone strikes, because of going after terrorists that kill quite a lot of civilians. How are you noticing that in these areas Americans are actually being received warmly because of this aid?
SCIUTTO: Well, we see them getting hugged. They're getting kisses literally on the ground from these troops and thanks, gratitude for this aid that they're in desperate need of.