U.S. officials seeking to simultaneously prevent terror attacks at home and avert war in South Asia face a difficult question: should we pressure Pakistan to crack down on anti-America Muslim extremists, or pressure Pakistan to crack down on anti-India Muslim extremists?

Although the goals are not mutually exclusive, an effort to stop Muslim extremists in the disputed province of Kashmir could require Pakistan to pull troops away from the country's border with Afghanistan. Pakistani President Pervez Musharraf moved the troops there due to U.S. pressure to catch fleeing Al Qaeda terrorists.

For the time being, the U.S. is focusing on convincing Musharraf to crack down on extremists who are pressing for war with India, Secretary of State Colin Powell said last week.

Powell acknowledged that if Musharraf assents but pulls troops from the Afghan border in the process, "it takes away from our own campaign against terrorism."

Both Pakistan and India are U.S. allies, but the two have a long history of disputes, with most stemming from the disputed ownership of mostly-Muslim Kashmir. India's population is primarily Hindu.

The countries are on full military alert due to escalating attacks by Muslim extremists against India. India alleges that the attackers are based in Pakistan and says that Musharraf is allowing the extremists to reach Kashmir.

Last week, President Bush warned that Musharraf must "live up to his word" and stem the flow of extremists.

Prior to the Sept. 11 attacks, Musharraf mostly tolerated Muslim extremists, with Pakistan's intelligence service even supporting the Taliban in Afghanistan.

After the attacks and with aid incentives, Musharraf agreed to assist the U.S. in its hunt for Usama bin Laden and members of Al Qaeda by massing troops on the Afghan-Pakistani border to catch fleeing enemy fighters.

India criticizes Musharraf's handling of the effort, saying that despite mass detention of extremists, many were subsequently released.

Another factor that U.S. officials must take into account is that a crackdown on anti-India extremists could erode Musharraf's support at home, including with the generals he requires to stay in power.

Even more worrisome, militants already in the area, who hate Musharraf as much as they hate the United States and India, "can engage in activities on their own that could galvanize the conflict," even if Musharraf tries to stop them, said Andrew Hess, a Pakistan expert at Tufts University's Fletcher School.

In their hope to destroy Musharraf and India and create a Muslim vs. non-Muslim split worldwide, "they may be willing to go to radical lengths to encourage war, even nuclear war," Hess said, even if that would destroy Pakistan, too.

The Associated Press contributed to this report.