Officials involved in the debate said that the question of attacking Pakistani militants was especially delicate because some militant leaders, including Haqqani, were believed to still be on the payroll of Pakistan's intelligence service, called the Inter-Services Intelligence Directorate, or another part of Pakistan's intelligence apparatus.
For years the intelligence services have relied on a web of sources among Pakistani militant groups to collect information on foreign groups like al-Qaida that have operated in the tribal areas.
A Pentagon adviser said that military intelligence officers in Afghanistan had drawn up the detailed list of potential targets that was discussed with Patterson. It is unclear which senior officials in Washington were involved in the debate over whether to authorize attacks.
One administration official said that the internal discussions in Washington involved President Bush's top national security aides and took place earlier this year.
Military and intelligence officials say that al-Qaida and its affiliates now have a haven to plan attacks, just as they used camps in Afghanistan before the attacks of Sept. 11, 2001.
Gen. Michael V. Hayden, the CIA director, said last month that the security situation along the Afghanistan-Pakistan border "presents clear and present danger to Afghanistan, to Pakistan and to the West in general, and to the United States in particular."
American officials involved in the discussions said that they had not ruled out striking Pakistani militants in the tribal areas. American forces in Afghanistan are authorized to attack targets in Pakistan in self-defense or if they are in "hot pursuit" of militants fleeing back to havens across the border.
American-led forces in Afghanistan fired artillery at what they suspected was a Haqqani network safe house on March 12 that an American spokesman said posed an "imminent threat." But the Pakistani army said the strike killed only civilians.
Administration officials say the risk of angering the new government in Pakistan and stirring increased anti-American sentiment in the tribal areas outweighs the benefits of dismantling militant networks in the region.
"It's certainly something we want to get to, but not yet," said one Bush administration official. "If you do it now, you can expect to do it without Pakistani approval, and you can expect to do it only once because the Pakistanis will never help us again."
