People assist a young man wounded in car bomb in Kashmir on Feb. 14. (Farooq Khan/EPA-EFE)

Kashmir has endured roughly 30 years of insurgency, and the region is almost tragically numbed to headlines about terrorism, turmoil and tragedy.

But what unfolded Thursday — the worst terrorist attack in decades — will fundamentally change both India’s internal policy within the state and its relations with Pakistan.

More than 40 paramilitary police officers were killed by a suicide bomber from the terrorist group Jaish-e-Mohammed, and Indians are apoplectic.

This is clearly an act of war. And the man reportedly behind it, Maulana Masood Azhar, is free and operating with absolute impunity in Pakistan. That he was released in 1999 from an Indian prison — in a swap deal for the safety of passengers taken hostage in a commercial airline — makes Indians even angrier.

Two decades later, Masood Azhar has not been brought to justice. Instead, he hides in plain sight in Bahawalpur, in Pakistan’s Punjab Province, and is now allowed to address huge Islamist militant gatherings over audio speakers in other parts of Pakistan.

There will almost certainly be a strong military response from India. In September 2016, when an army camp was assaulted by terrorists who had infiltrated from Pakistan into Kashmir, the Narendra Modi government sent in commandos to Pakistan to carry out targeted counterattacks. The scale of this attack is much bigger and, likely, so too will be the response from India.

Pakistan has long operated on the assumption that two nuclear nations will not and cannot escalate their conflict above a certain threshold. It is this calculation that emboldens Pakistan’s asymmetric war against India, in which terror groups are proxies for its deep state. Well before 9/11, India was already battling this terrorism — mostly alone.

Today, as condemnations pour in from countries across the globe, leading international powers must take their share of blame for their unwillingness or inability to draw a red line around Pakistan’s patronage of terror. India’s response should be calibrated, restrained and responsible. Modi will be under enormous pressure to react swiftly. More so because the ruling Bharatiya Janata Party has always claimed to be more nationalistic than the opposition. And with elections just a month or so away, the government has a short window to make its point.

While India and Pakistan have gone through several phases of breakdown and repair in their relations, this time the breach is much more severe. Among ordinary Indians, patience is wearing thin. All talk of dialogue and reconciliation — or even of a shared history — appears pointless when young men are routinely being killed by fundamentalists who have patrons across the border.

Indians are also exasperated at global double standards in the form of the United States’ relationship of convenience with Pakistan because of its interests in Afghanistan, China’s protection of Pakistan as it were its vassal and Saudi Arabia’s bankrolling of a flagging Pakistan economy. There is a growing sense that India should forge tactical new alliances — if the United States sulks over India and Iran’s growing collaboration so be it — or realize that it will always be left alone to fight for self-preservation.

There was already diminishing appetite for an internal dialogue process in Kashmir. And this attack may have eliminated it altogether. In an interview with me, the governor of the state, Satyapal Malik, lashed out at both major political parties in Kashmir for being soft on terrorism.

The attack has also brought home the very real problem of religious radicalism. The suicide bomber recruited by the Jaish was reportedly a 22-year-old named Adil Ahmad Dar, who lived just kilometers away from the site of the explosion.

Kashmir has seen a surge in local militancy, with educated, relatively well-off boys embracing not just the gun but also the idea of a Caliphate in Kashmir. Dar’s videos, which appear to have been filmed by the Jaish in advance, are now circulating on social media. He is strapped with weapons and explosives and exhorts others to join the “jihad.”

Many Kashmiris argue that talk of radicalism is an excuse to tar the larger political debate. This is simply not true. The growing and aggressive Islamist sentiment among an entire generation of young Kashmiris is very much part of the shifting sands in the valley. And it has dramatically shrunk the space for a rational conversation about Kashmir elsewhere in the country.

Arun Jaitley, a minister in the Modi government, warned that India will deliver an “unforgettable lesson” in retaliation.

In an angry, outraged and cynical country, this is unlikely to be an overstatement.

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