THE ASSOCIATED PRESS

The flames towering over Karachi’s international airport before dawn on Monday made one thing clear: Pakistan’s war on terror extends well beyond the tribal areas along its border with Afghanistan. That makes the fight much more complicated. It will require more than troops and tanks to win.The Pakistani Taleban claimed credit for the deadly assault on the country’s biggest airport. In recent months, the debate over how to confront the Waziristan-based insurgents has revolved around whether to negotiate a political truce or to crush them with force.

Both approaches have failed in the past: Cease-fires have given the militants time and space to regroup, while army offensives have only driven them into Afghanistan or scattered them into Karachi and other cities. Now authorities seem to be hoping to split the movement to isolate its most hard-core wing.

Even when effective, such measures address only part of the problem. By now, Pakistan’s militant nexus encompasses many allied groups beyond the Tehreek-e-Taleban Pakistan (TTP). Ethnic and sectarian attacks in Karachi, the world’s most violent megacity, rose 90 percent last year, causing a record 2,700 casualties. Many of the city’s deadliest gangs claim at least tacit support from local politicians.

Pakistani authorities can no longer afford to draw distinctions between these groups, or between “bad” militants and “good” militants like the Afghan Taleban, who supposedly direct their attacks outside the country. While in some cases extremist groups battle one another for turf and control over lucrative criminal operations, at least as many share resources, intelligence, recruits, funding and training. These networks are now embedded in all of Pakistan’s major cities, and they greatly enhance the TTP’s ability to carry out attacks like Monday’s assault.

Tolerating even some of these groups allows all of them to grow. Cities in particular have become fertile recruiting grounds. Rapid urbanization — Karachi’s population swelled 80 percent in the 2000s, the biggest increase of any city in the world — has increased the ranks of disaffected, unemployed young men. Already, according to some estimates, the Pakistani Taleban control as much as a third of Karachi, an area that includes some 2.5 million people and accounts for much of the group’s funding. Pakistan needs to rethink how it conducts this fight. Authorities have thus far treated the problem of urban militancy as an extension of the battle in the tribal areas — a matter for paramilitary troops with broad, easily abused powers. This has bred resentment and led to allegations of extrajudicial killings, without notably diminishing the militant threat. A better long-term strategy would be to rejuvenate Pakistan’s demoralized and outgunned police forces.

The police also need to be better insulated from political interference. And while their investigative skills can be admirable, they need better resources, including a centralized counterterror data bank that includes voice matching, fingerprinting, DNA analysis and other forensic information. Most of all, they need a clear signal from national political leaders that once-protected militant groups will no longer be tolerated, any more than the TTP is. Only if police are encouraged to go after all extremist groups will they be able to dismantle the networks that have rooted themselves in cities such as Karachi, Lahore and Quetta. It’s true that this is a war, but the militants are no warriors. They are thugs and criminals. It’s time Pakistan treated them as such.