A photo taken Sunday from space shows a fifth of the country underwater. Government aid has reached only 500,000 of the 20 million people affected. Three and a half million children are at risk of disease.
The United States is rushing to help for humanitarian and strategic reasons, CBS News Correspondent Richard Roth reports.
Ninety nine feet long with thundering twin engines, American Chinook helicopters have helped move almost 5,000 flood victims. A former U.S. ambassador recalled the last time it was like this.
"President (Pervez) Musharraf at that time would point to them and say, 'Here comes another squadron of the angels of mercy,'" said Wendy Chamberlin, now president of the Middle East Institute.
That was after a devastating earthquake in 2005, when so-called "Chinook diplomacy" boosted America's standing in a country widely seen as a reluctant ally in the war on terror.
Now, with the flooding, the stakes maybe even higher.
"I don't think it will happen, but I think we need to plan for a worst-case scenario, a nightmare scenario, and that nightmare scenario is an al Qaeda, Taliban-type takeover of the government," Chamberlin said.
Already weak and unpopular before the floods broke, the Pakistani government's been slow to get aid to where it's needed.
Keeping the country from drowning in its distress is crucial to U.S. policy.
"An extremist government in Pakistan would have its finger on the atomic weapons arsenals," Chamberlin said.
Hard line Islamist groups have been helping flood victims, but the battle for hearts and minds has by no means been lost, according to the current U.S. ambassador in Pakistan.
"Stories about extremist organizations being the only players out there are greatly exaggerated," Ambassador Anne Patterson said.
What's not overstated is the scale of the disaster. The floods began three weeks ago, and there are millions still in Pakistan struggling to survive.
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