The Pakistani mission is part of a diplomatic effort to bring bin Laden to justice and persuade the Taliban to help destroy his organization. If the Taliban refuse, they will suffer "the full wrath of the United States," Secretary of State Colin L. Powell said yesterday.
Powell, interviewed on CNN's Late Edition, said the United States will make its approach to the Taliban in the next few days.
At the White House, President Bush said again that the war against terrorism will be a long one and urged the American people to be patient, return to their jobs today and rebuild a sense of normality.
"Today, millions of Americans mourned and prayed, and tomorrow we go back to work," he said late yesterday as he returned from the Camp David presidential retreat in Maryland, where he had been huddling with his top national security advisers since Friday.
"Our nation was horrified, but it's not going to be terrorized," he said.
Of the terrorists who planned Tuesday's attacks on the World Trade Center towers and the Pentagon, he said, "They have roused a mighty giant."
The remark recalled in words and circumstance a statement by Adm. Isoroku Yamamoto, who reluctantly planned the Japanese attack on Pearl Harbor in 1941: "I fear that all we have done is awaken a sleeping giant and fill it with a desire for vengeance."
Earlier in the day, the president's top aides flooded the airwaves, talking tough, warning that a response to the attacks might not come soon and that it would require a multipronged effort, including diplomatic and economic measures.
"It's not a matter of days or weeks; it's years," Defense Secretary Donald H. Rumsfeld said. "It will take a broad, sustained effort that will use our diplomatic, our political, our economic, our financial strength, as well as our military strength and unquestionably unconventional techniques."
Vice President Dick Cheney revealed that Bush on Tuesday ordered F-16 fighter jets to shoot down any commercial aircraft over Washington that seemed to threaten the nation's capital.
"If they wouldn't pay any attention to instructions to move away from the city, as a last resort our pilots were authorized to take them out," Cheney said, speaking from Camp David, where he was moved last week for security reasons.
Other fighter aircraft were patrolling the skies from New York to Washington after the attack. Those patrols have been expanded to 26 bases that are able to scramble fighter jets within 15 minutes if there is another airborne threat.
"The possibility clearly exists that there could be additional terrorists out there," Cheney said on NBC's Meet the Press.
Bin Laden issued a statement yesterday denying involvement in the attacks. "I have not carried out this act, which appears to have been carried out by individuals with their own motivation," said the statement, broadcast by Qatar's Al-Jazeera satellite channel.
Bin Laden said he was used to the United States accusing him every time "its many enemies strike at it."
Bush brushed off the denial, saying there is strong evidence that bin Laden and his terrorist network, Al Qaeda (the Base), were behind last week's attacks by hijacked American passenger jets.
"No question he is the prime suspect, no question about that," Bush said on his return to the White House.
Bush reaffirmed his vow to track the terrorists down. Cheney went further, hinting that bin Laden could face assassination, which is barred by a 1976 presidential executive order. Asked on Meet the Press whether he would like to have bin Laden's "head on a platter," the vice president replied, "I would take it today."
Pakistan, which agreed under strong pressure Saturday to cooperate fully with the new U.S.-led anti-terrorism campaign, sent the delegation to meet Taliban leaders in Kandahar rather than Kabul, Afghanistan's capital. Kandahar is where the movement's leader, Mullah Mohammed Omar, is based.
CNN reported that the Pakistanis will convey an ultimatum warning that if bin Laden isn't handed over in three days, U.S. military action could follow. A Pakistani Embassy official in Washington said he could not confirm that.
"We will be urging the Taliban leadership ... to accede to the demand of the international community. The demand is to bring to justice the perpetrators of the crimes that have been committed [and to] hand over the person that they are harboring, Osama bin Laden, so that he is brought to justice," Pakistan's ambassador to the United States, Maleeha Lodhi, said on CNN.
The Pakistani mission is the first step in what could be a drawn-out negotiation involving bin Laden, the Taliban, Pakistan and the United States, said Robert B. Oakley, a former U.S. ambassador to Pakistan. "Osama bin Laden will try to persuade the Taliban to continue to protect him and if necessary to go to war," Oakley said.
It is in the interest of the United States to attempt such negotiations while not backing down in its drive to eliminate bin Laden and his movement, Oakley said, adding, "We don't want this to be a war against the Afghans, or even the Taliban, if we can avoid it."
L. Paul Bremer, a former U.S. ambassador-at-large for counterterrorism, said he is skeptical that the talks will produce anything, but he said they show that Pakistan is "willing to make a move" and that the Bush administration is exploring options other than force. Eventually, the United States won't succeed in blocking terror unless "we get rid of the Taliban," Bremer said.
Bin Laden provides money and military support to the Taliban in exchange for sanctuary and training camps, U.S. officials and regional specialists say.
Cheney said nations supporting terrorists -- he singled out Afghanistan, which is providing a refuge to bin Laden -- will face "the full wrath of the United States of America."
"We will in fact aggressively go after these nations to make certain that they cease and desist from providing support for these kinds of organizations," the vice president said.
Attorney General John Ashcroft, also speaking from Camp David, said he would ask Congress to expand the Justice Department's authority to battle terrorism.
Ashcroft said on Fox News Sunday that he wants to broaden wiretap authority while strengthening controls on money-laundering and immigration.
He said he also wants to empower law enforcement agencies to use against terrorism some of the tools used in drug and organized-crime investigations.
Asked whether such new authority might curb civil liberties and individual rights, Bush said, "We have to be alert in America. We're a nation of law, a nation of civil rights. We're also a nation under attack."
Powell said it is time to examine all laws and executive orders pertinent to terrorism that govern law enforcement and national security agencies, including a 25-year-old prohibition against assassinations.
"We are examining everything: how the CIA does its work, how the FBI and Justice Department does its work," Powell said on CNN's Late Edition. There are also calls on Capitol Hill to scrap the assassination ban, with lawmakers planning a hearing this week.
Although the ban could be lifted by the president, some administration officials want to discuss any changes with Congress.
The administration's new threats against bin Laden emerged as Justice Department officials said three of the "black boxes," containing flight data from two of the hijacked planes, were being analyzed. A fourth box, the cockpit voice recorder from the airliner that hit the Pentagon, was too damaged to be useful.
The criminal investigation into the attacks continued yesterday across the country. Investigators have begun to interview the 25 people detained by the Immigration and Naturalization Service and continue seeking more than 100 others for questioning.
The Justice Department reported over the weekend that it had taken into custody two material witnesses wanted for questioning and considered flight risks. Some news organizations said last night that two additional witnesses had been detained, but Justice Department officials would not confirm those reports.
All of the affidavits prepared in the case for search warrants or warrants to detain witnesses have been filed under seal.
Transportation Secretary Norman Y. Mineta said yesterday that he has created two rapid-response teams to review airport and airliner security issues and make recommendations for improvements by Oct. 1
The airliner task force is expected to focus on airport and plane security, including methods for denying access to cockpits.
In New York, rescue crews continued digging through the rubble that was the World Trade Center as the number of people presumed dead in the attacks at the twin towers continued to climb.
Mayor Rudolph W. Giuliani said 5,097 people have been reported missing at the site, 100 more than in previous counts. Of the 180 people confirmed dead, 115 have been identified, Giuliani said.
Over the weekend, there seemed to be glimmers of hope, with reports late Saturday of the sounds of trapped people knocking at the site. Giuliani said the reports were untrue.
"The recovery effort continues, and the hope is still there that we might be able to save some lives, but the reality is that in the last several days we haven't found anyone," Giuliani said. The false reports, he said, were probably made because "there's so much of a feeling and so much of a sense that we want that to be true," he said.
Last week, Congress approved $40 billion in spending, half of which will be used for emergency relief efforts in New York. Much of the remaining $20 billion will be used by the Pentagon to beef up anti-terrorist protection at bases and military installations and to purchase weaponry and equipment, including unmanned drones and missiles, and night vision goggles and sophisticated radios.
Some of the money will be used for training special operations troops to head into hilly terrain like that of Afghanistan and root out terrorists.
Asked yesterday about a military response to terrorism, Rumsfeld said that "a lot of it will be special operations," noting that long-range weaponry will not work in such a war.
"Cruise missiles do not get people operating in the shadows," he said.
About 50,000 active and Reserve personnel are part of such commando-style units, which include the Army's Green Berets and Rangers,and the Navy's SEALs.
Though terrorists do not have armies, navies or air forces, the nations supporting them have such "high value targets," Rumsfeld said.
The defense secretary also said yesterday that the security alert and threat condition had been reduced at the Pentagon and for U.S. forces. At the Pentagon, the threat condition dropped from Delta, the highest, to Charlie, Rumsfeld said.
Last week, the president authorized a call-up of 50,000 National Guard and Reserve troops to provide additional security. Pentagon officials expect to begin soon calling about 35,000 of those to active duty, 13,000 of them Air Guard and Reserve pilots and ground crews for possible combat air patrols.
Pentagon officials said they expect additional call-ups in the coming months. Rumsfeld also was asked yesterday about the possibility of a draft and said nothing had been ruled out.
Cheney said yesterday that some evidence linking bin Laden's organization to the suicide attacks comes from ties of some of the hijackers to the terrorists involved with the bombing of the USS Cole in October last year, which killed 17 sailors. Friday, the Cole quietly set sail from a shipyard in Mississippi where it was being repaired.
Meanwhile, Wall Street held its breath for this morning's scheduled 9:30 opening of the stock markets, which have been closed since Tuesday's attacks.
Wire services contributed to this article.