Afghanistan's Border Battle: Ground War In Pakistan

ISLAMABAD, Pakistan, Dec. 7, 2010— -- Senior United States officials fear that despite billions of dollars and countless efforts trying to expand their relationship with Pakistan, a single successful terror attack launched from Pakistan could cause the relationship to fall apart -- and lead the United States to consider widening airstrikes and even launching special operations raids inside Pakistan.

"If there's an attack traced back to Pakistan, all bets are off," says a senior Western official who insisted on anonymity.

United States, Afghan, and many Pakistani officials believe the key to fighting the war in Afghanistan is eliminating the sanctuaries the Taliban enjoy inside Pakistan. But that is a complex, long-term effort, and United States officials are becoming increasingly impatient. That, in turn, is straining an already tense relationship with Pakistan, officials in both countries acknowledge.

"There have been compulsions on the [U.S.] military brass in Kabul and consequently, pressure on the Pakistani military, and that hasn't suited us at all," a senior Pakistani military official told ABC News. He accused the U.S. of "passing the buck" and making the Pakistani military "the scapegoat."

The tension is most strained over the semiautonomous tribal area of North Waziristan along the Afghanistan border. Residents of North Waziristan interviewed for this article describe an increasingly lawless area where, as one of them put it, "every nationality under the sun" is represented in a sort of melting pot of militant groups.

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United States officials believe the leaders of the Haqqani militant network, based out of North Waziristan and long a threat to U.S. troops in Afghanistan, is increasingly becoming international in nature, providing safehavens to militant groups, including al Qaeda, that want to attack Western targets.

For that reason the Central Intelligence Agency has dramatically increased attacks by unmanned aerial drones inside Pakistan. More than 80 strikes have been launched in North Waziristan this year alone, about double the number of strikes as launched anywhere during the entire Bush administration.