Those warnings are detailed in a series of contemporaneous written accounts, obtained by The Washington Post, chronicling three years of often-contentious meetings involving top officials of both countries. Confirmed by U.S. and Pakistani participants, the exchanges portray a circular debate in which the United States repeatedly said it had irrefutable proof of ties between Pakistani military and intelligence officials and the Afghan Taliban and other insurgents, and warned that Pakistani refusal to act against them would exact a cost…

“You can’t continue business as usual,” said one of several senior administration officials who discussed the sensitive issue only on the condition of anonymity. “You have to somehow convey to the Pakistanis that they’ve arrived at a big choice.”

“People who were prepared to listen to [Pakistan’s] story for a long time are no longer prepared to listen,” the official said.

But few officials are eager to contemplate the alternatives if Pakistan makes the wrong choice. No one inside the administration, the official said, “wants to make a fast, wrong decision.”