This year the spring offensive by the Taliban and other insurgent groups has a new and terrifying face: the insurgents are using suicide bombers who create high casualties to sow terror and are planning an assassination campaign as well, Afghan and American military analysts say.

The insurgents' deadly bet is that fear will trump anger and that Afghans will lose any faith they had in their government's security forces and eventually turn to the Taliban.

“You have to ask yourself, ‘If you were the Taliban now, what would you do?' ” said Gen. Jack Keane, who retired from the Army in 2003 and is now a consultant to Gen. David H. Petraeus, the North Atlantic Treaty Organisation (NATO) commander for Afghanistan.

Given the massing of NATO forces in the south, the answer appears to be attack the urban, civilian population, creating widespread insecurity in an effort to reinforce the existing resentment of foreign troops and doubts about President Hamid Karzai's government.

In less than four weeks, 116 Afghans have died in seven suicide attacks, most recently in Faryab Province on February 26. Two of the attacks, one in Jalalabad on February 19 and another in Kandahar on February 12, involved multiple assailants and were carefully choreographed and skillfully timed to obtain a high death toll and maximum media coverage. In at least one case, the mission was carefully rehearsed.

This is a striking change from Afghan suicide bombings of just six months ago, in which the bombers exacted few casualties.

These new tactics highlight the challenge of an adaptive insurgency with a reservoir of potential fighters, many of them madrasa students in Pakistan's tribal areas. They show too the increasingly integrated network of insurgent groups that lend their expertise to one another as well as the difficulties the Afghan government has had in rallying its own people to fight them.

President Karzai has compounded the problem, some Afghan analysts say, by insisting that the Taliban are not to blame for the violence and that they are “upset brothers” rather than mortal enemies.

Underlying the latest attacks are the region's geopolitics. Both Pakistan and Iran are known to be supporting the Taliban and play out their antagonism to the United States on Afghan soil. “You have to see these attacks in the broader strategic context,” said Haseeb Humayoon, the director of a risk consulting firm here.

A period of relative calm last year in Afghan cities coincided with an easing of tensions between the Afghans and Pakistan over negotiations with the Taliban. Now the Afghans appear to be trying to negotiate with the Taliban on their own, and there is talk of permanent American bases here, which Pakistan and Iran see as a potential loss of their influence.

“Our neighbours interpret that as Afghans' seeking guarantors of security other than them,” Mr. Humayoon said.

“Both the international military and our own government are distracted,” he added. “Our government is not focussing enough on rallying people against these forces, and the international military coalition has not focused enough on Pakistan.”

American commanders play down the significance of the attacks in terms of the overall fight in Afghanistan, but Afghan security officials say they see a troubling and potentially crippling development. “It's not that the American surge operations will be affected by this directly,” said a former Afghan security official. Rather, he predicted that the suicide attacks could preoccupy Afghan security leaders, diminishing their ability to contribute to the fight in the south.

The Americans had not expected the suicide bombings on this scale but were bracing for assassination attempts this spring against officials, said Rear Adm. Gregory J. Smith, NATO's chief of strategic communications.

The Taliban in the past have been careful not to single out civilians, although civilians are often killed in attacks. At least some Taliban factions seem worried about the latest tactics. Zabiullah Mujahid, the Taliban spokesman for the north and east of the country, said an investigation was under way into the Jalalabad attack, which killed 40 people, nearly half of them civilians.

“We are taking this issue seriously as we have appointed a delegate to assess the civilians casualties,” he said. “We are not happy when there is even one civilian lost.”

Despite such statements, attacks on civilians are clearly on the rise and the sophistication of the suicide bombings has been striking, Admiral Smith said. American and Afghan officials now believe that Lashkar-e-Taiba (LeT), the group that planned the attacks in Mumbai, India, in 2008, has been working with the Haqqani network, which is based in North Waziristan. Lashkar-e-Taiba specialises in planning complex suicide attacks.

“The suicide bombings are, we believe, predominantly requested and funded by Haqqani but facilitated by LeT and AQ,” said a senior American military official, referring to Lashkar-e-Taiba and Al Qaeda. “The latter groups provide bombers and material in exchange for money. Haqqani chooses targets.”

The bombing of the Kabul Bank branch in Jalalabad used a formula Lashkar-e-Taiba has used elsewhere: multiple attackers, a first bomber to clear the way for the others and the holding of one bomber in reserve to attack the police and medical workers who arrive to help. Other signatures included having a suicide bomber on a cellphone with a handler, as was the case in the Mumbai attacks.

What cannot be ignored, however, is the situation across the border in Pakistan. While American troops have made clear gains in uprooting the Taliban from Kandahar and large areas of Helmand Province, Pakistan has not made similar strides in ousting the Taliban from the tribal areas, according to analysts here. The Haqqani network, among the most brutal, remains anchored in North Waziristan despite a stream of drone strikes by the Central Intelligence Agency.

And in bad news for Afghanistan, a little-noticed peace deal took place late last year between the Haqqani network and Shiite tribes in the Kurram Agency in Pakistan, which opened up a new route for Haqqani agents to enter Afghanistan, American and Afghan intelligence officials said. A number of fighters have been observed crossing the border over the past several weeks, American intelligence officials said.

No one yet seems to have figured out how to deal with the two largest underlying problems: the poor performance of the Afghan government, which makes many of the country's citizens reluctant to fight for it, and the millions of Pashtuns in the tribal areas who feel they are unrepresented and even discriminated against and are willing to cross the border to fight in Afghanistan.

“You still have two major factors,” General Keane said, “the ineffectiveness of the central government and the Pakistani sanctuaries.”

The situation is strikingly reminiscent of Iraq in 2005, when that country's cities were gripped by violence, the government was unable to keep the people safe and fighters flowed in from other countries. It took four years to stem that violence , and an influx of troops like the one that Americans have now carried out in Afghanistan. The rash of recent bombings risks undermining the psychological advantage that had come with increased American troop strength in southern Afghanistan. (Eric Schmitt contributed reporting from Washington.)— © New York Times News Service

More In: Comment | Opinion