Key advisers to the Obama administration are warning of a violent summer for Pakistan as its forces prepare to enter the rugged tribal areas of North and South Waziristan for a showdown with the Taliban and al Qaeda.
The two Waziristans form a nexus for Taliban fighters along the Afghanistan-Pakistan border. And with the U.S. surge in Afghanistan under way, a Pakistani military success on its side of the border could represent the turning point in a war that has gone badly for all three nations.
Pakistan's army has been humiliated repeatedly by Taliban fighters in past, especially in the Waziristans, making the upcoming offensive a test for the key U.S. ally.
Bruce Riedel, a Brookings Institution scholar who chaired a review of Pakistan-Afghanistan strategy for President Obama in the early days of his administration, warned that Pakistan faces a tough enemy.
"We can certainly hope that Pakistan has turned the corner," Mr. Riedel said. "But experience should encourage us to be somewhat skeptical."
He added: "We've seen some encouraging signs, but it's a little premature to call this a victory yet."
Pakistani troops have recovered much of the Swat Valley, an area much closer to the capital, Islamabad, that was overrun by Taliban militants earlier this year.
But it has yet to resettle hundreds of thousands of refugees from the former tourist area, an effort that will require a permanent military presence to keep the Taliban from returning. Apart from military muscle, Pakistani officials have outlined a broader strategy that includes investment and development in hopes of promoting long-term stability.
"Pakistan army officials even say that the military is only one part of a much broader solution that needs to be met," Mr. Riedel said.
Pakistani officials call upcoming operation in the Waziristans "matter of survival" for their country, as it will target Pakistan's top Taliban commander, Baitullah Mehsud.
Mehsud has been the mastermind behind terrorist bombings that have claimed hundreds of lives in Pakistan in recent years, including retaliatory attacks for the Swat offensive. Barely a week goes by without a bombing or terrorist attack by his fighters.
Mehsud is also thought to be behind Tuesday's assassination of Qari Zainuddin, a rival Taliban leader in the Waziristan region.
Pakistan has been pounding the region from the air for several weeks, as have suspected U.S. drones.
"The Pakistan military is preparing for a bigger military offensive in the area," said a senior Pakistani official, on condition of anonymity because of the sensitive nature of military operations.
"Baitullah Mehsud is certainly a target on our list, and any al Qaeda operatives and supporters who are in our way will be targets for us as well," the officer said.
The U.S. military reportedly launched missile attacks this week targeting Mehsud and his allies.
Missiles apparently fired by unmanned aircraft first struck a purported Taliban training center in South Waziristan, then another barrage rained down on a funeral procession for some of those who had been killed, Associated Press reported.
The second attack appeared to be the deadliest U.S. missile attack ever on Pakistani soil, killing an estimated 80 people, according to the AP. Mehsud reportedly escaped.
A U.S. intelligence official for South Asia, who spoke on condition that he not be named because of his work, said the upcoming operation comes amid signs of improvement in Pakistan's counterinsurgency capability.
The officer cited three reasons for optimism: the size of the Pakistani force involved, a shift in Pakistani public opinion to support the effort and expectations of new tactics adopted by the Pakistani military to "minimize some of the problems that have been associated with past military operations."
Recent Pakistani military operations in the Swat Valley have been hailed as a success by the Pakistani government and U.S. defense intelligence officials, who concur that the Pakistan military has cleared more than 80 percent of the militants from that region.
The question U.S. officials ask is whether Pakistan can hold areas it seizes from militants, which would mark a shift from past operations where Pakistan's military would fight, leave an area and the Taliban would return.
That change in strategy is a hopeful sign, defense intelligence officials told reporters at the Pentagon last week. They spoke to reporters on condition that their names not be revealed because of the sensitive nature of their jobs.
Recent terrorist attacks since late May have been attributed to the Taliban retaliation over the government offensive in Swat.
Once the Waziristan offensive begins, Mr. Riedel said the militants will push back hard.
"The Taliban and al Qaeda recognize that they are in a fight for the future of Pakistan," he said.