Pakistan soldiers cordon off the area after a bombing in Peshawar on Feb. 15. (Mohammad Sajjad/AP)

When the Pakistan army announced that it was launching a nationwide military operation to “indiscriminately” eliminate the threat of terrorism from the land, the adverb had a precise and politically loaded meaning.

For the first time, after years of appeasing certain Islamist militant groups for political and religious reasons, the government has reluctantly agreed to allow the armed forces to enter Punjab province, authorized with special powers to hunt down, arrest and shoot suspected militants.

Punjab is the political stronghold of Prime Minister Nawaz Sharif and his ruling party, the Pakistan Muslim League-N. It is also the home of a variety of Islamist groups, including mainstream religious parties, sectarian movements officially banned for their violent methods, and anti-India militants who have been accused of a 2008 terrorist siege in Mumbai. 

None of these groups appear to have been directly involved in a five-day spate of suicide bombings that shocked the nation last week, including one at a Sufi shrine full of devotees that killed 86 people. The attacks were mostly claimed by an Afghan-based militia linked to the Islamic State, which declared it was starting a war against the Pakistani government. 

But the hodgepodge of Islamist movements based in Punjab, although attractive to many conservative Muslims and in some cases used as proxies in Pakistan’s rivalry with next-door India, are increasingly seen as part of a larger, collaborative threat by Islamist extremists to Pakistan’s stability, global stature and democratic way of life.

“In Punjab, particularly in southern Punjab, there are sanctuaries of hard-core militants which have not been targeted before,” said Amjad Shoaib, a retired army general and defense analyst. “This time they will be taken to task, and that will help a lot in eliminating terrorism not only from Punjab but other parts of country.”

After the recent attacks, which rocked the nation and embarrassed its new army chief, the military embarked on a series of raids and arrests last weekend. Swooping into suspected militant hideouts and supportive communities, from Karachi in the south to border tribal areas in the north, the military claimed to have killed more than 100 terrorism suspects in three days.

But they did not touch Punjab. Even though one of the suicide bombs was detonated in a crowded plaza in downtown Lahore, its provincial capital, and police rounded up and arrested numerous suspects, the region remained off-limits to military forces. 

The reason was essentially political. All of the extremist groups based in Punjab have served some useful purpose to the Sharif government and its control of the province. Some have delivered votes to the Muslim League, which hopes to see Sharif reelected next year. Some banned Sunni groups, such as Lashkar-e-Jhangvi, have been tolerated as anti-Shiite but not anti-government, and some have deflected pressure by changing their names. 

Jamaat-ud-Dawa, once known as Lashkar-e-Taiba, has helped rally citizens to the national cause of liberating the border region of Kashmir from Indian control. In a rare step to curb the group last month, the Sharif government placed its leader under house ­arrest, but it has never tried him on charges from India that he masterminded the 2008 siege of Mumbai.

Critics have been protesting this flirtation for years, warning that it could encourage the “Talibanization” of Pakistani society and arguing that despite their different agendas, the extremist groups share common beliefs, can easily form alliances of convenience and can be difficult to put back into a box once they gather strength and support. 

And even though the groups that claimed last week’s bombings were based in Afghanistan and were allied with the Islamic State, U.S. officials have expressed concerns about a growing “convergence” among various violent groups that operate in the ­Afghanistan-Pakistan region and appeal to the same population of potential recruits. 

In an interview published Wednesday by a terrorism study center at the U.S. Military Academy, Gen. John W. Nicholson, commander of U.S. forces in Afghanistan, noted that 20 of the 98 groups the U.S. government has designated as terrorists are located in the region — “the highest concentration anywhere in the world.”

Nicholson said that because these groups exist in a common “medium” — with large numbers of jobless youths, the presence of criminal activity, and extremist teachings in some religious seminaries — “it creates kind of a petri dish within which these different strains of terrorism” can “converge, recruit and morph into more virulent strains.”

Still, it took a week of high-profile bombings, a surge of public criticism and a private meeting between the army chief, Gen.­ ­Qamar Javed Bajwa, and senior officials in Punjab — where the top elected official is Sharif’s brother Shabbaz — to persuade the government to acquiesce. 

Army officials said the new operation, named “Reject Disorder,” would include sending 2,000 army rangers into Punjab for the next 60 to 90 days. Unlike previous army operations in other parts of Pakistan that have chiefly used force to flush out or kill militants, officials said, this one will be based mostly on intelligence gathering. Its mission will also include “deweaponizing” extremist groups, which could entail confrontations at heavily armed compounds. 

Some analysts said there are ambiguous signs of how much leeway the troops will be given by provincial leaders, who were forced by circumstances to go along with the military’s plan but have insisted that the rangers’ role will be limited. The specialized forces stirred controversy when sent to restore order in the violent and crime-plagued city of Karachi.

Among the public, although some critics have expressed concern about the risk of extrajudicial killings and other abuses, the army’s announcement has been met with swift and widespread approval.

“We wholeheartedly support” the decision, wrote the editors of the Express Tribune news outlet Thursday. The rangers, they urged, should resist political pressure and come down hard on the “snakepits of south Punjab” that function as “rear-echelon support” for other militant groups and as planning and logistics hubs for terrorist operations across the country. The editors added that they “look forward to reporting the excision of the cancer.”