Amb. Richard Holbrooke on Pakistan: ‘Worst Floods Imaginable’

Ambassador Richard Holbrooke painted an ugly picture of the devastation from the floods in Pakistan that have left 4 million people homeless.

The special envoy to Pakistan and Afghanistan said they are "the worst floods imaginable," affecting 20 million people, submerging an area the size of Italy and ruining much of the county’s infrastructure.

"We don’t know how many hundreds of miles of roads have been destroyed, we know that hundreds and hundreds of bridges have been wiped out,” Holbrooke told me on "GMA." "All of last year’s reconstruction efforts have been wiped out."

The ambassador said the U.S. has been "first with the most" aid to the country – and said it could help give America’s unpopular image a makeover in Pakistan. The U.S. has pledged $90 million in aid and Secretary Clinton is expected to announce additional aid at the United Nations today.

But the crisis in Pakistan is more than humanitarian– it could also impact our national security.

“We are not oblivious to the political and security implications of this,” Holbrooke said.

“Pakistan is not just another country that has been hammered by a tragedy, it is at the epicenter of global terrorism,” he said.

ABC News has reported on a charity arm of an Islamic extremist group that is operating a relief camp in Pakistan. Holbrooke said that the opportunity for militant groups to take advantage of the crisis and build support is an issue they are “concerned” about — but not what they are concentrating on.

“Right now we’re focused solely on the emergency rescue and relief mission…My greatest concern governmentally, George, is that local governments have been put underwater as well. But I stress again, America is leading the effort and every individual American can do something on their own,” he said.

Click here to find out how you can help the victims in Pakistan.

–George Stephanopoulos