A Taliban spokesman claimed credit for the attack and said the embassy was the intended target.
In July of 2008 militants rammed the same embassy with a car bomb that killed 60 people. Both US and Indian officials later claimed they had uncovered evidence that Pakistan's spy agency was in contact with the attackers.
That recent history and the long simmering Indian-Pakistan conflict over possession of Kashmir had some Indian security analysts pointing Pakistan's way on Thursday.
"I would suggest this is the same thing. Pakistan simply doesn't want any Indian presence in the region," says Ajai Sahni, director of the Institute of Conflict Management in New Delhi. Asked how that could impact India-Pakistan relations, Dr. Sahni replied, "What relations? This is just a cyclical game. A new attack doesn't change anything."
Others have more doubts. "Given the divide between Taliban and Pakistan in recent years, particularly since Pakistan troops are fighting Taliban forces in Pakistan, I would rather see it as the Taliban's own initiative," says Suba Chandran, assistant director of the Institute for Peace and Conflict Studies in New Delhi.
But he agrees with Sahni that if Pakistani elements were involved it would barely register diplomatically, since the relationship cannot get much worse.
Does Washington care?
While it's common to hear sighs of resignation from the Indian establishment about Pakistan, the reaction could run hotter in Washington. After last year's attack on the Indian embassy, US officials leaked intelligence intercepts that pointed Pakistan's way, a move that marked a nadir in relations between the two countries.
By all accounts, the trust between Washington and Islamabad has markedly improved over the past half year, following a series of military offensives inside Pakistan aimed at routing anti-government Taliban. US-Pakistani intelligence coordination is also credited with successful drone strikes in Pakistan's tribal belt that have killed Pakistani Taliban chief Baitullah Mehsud and Tahir Yuldashev, the head of the Al Qaeda-linked Islamic Movement of Uzbekistan.
But Thursday's bombing could remind Washington that Pakistan still has done little to rein in militant groups whose attacks are focused outside Pakistan. Pakistani intelligence has traditionally used such groups to advance its interests in Afghanistan and to put pressure on India. The group blamed for the first Indian embassy attack as well as numerous other attacks in Afghanistan – the Haqqani Network – operates in Pakistan's North Waziristan tribal agency.
Meanwhile, the Pakistani military is upset with Washington over conditions attached to a $7.5 billion US aid package. In an unusually strong public statement, the Army's top commanders released a press statement expressing "serious concerns" that some of the bill's clauses would hurt "national security."
The spat over the aid comes at a bad time. The Pakistani military stands poised to launch an offensive in the South Waziristan tribal area, a fight that Pakistani security experts say will require close cooperation between Pakistan and the US, which flies drones over the region.
The Taliban have plenty of their own reasons for attacking the Indian embassy. India supported the Northern Alliance when the Taliban controlled Kabul. And since 2001, India has contributed more than a billion dollars in aid to Afghanistan's reconstruction – a large sum for New Delhi and a significant boost for the government in Kabul. Indian contractors are building infrastructure, while Indian experts are helping train Afghanistan's military officers. New Delhi has avoided sending its military to fight, however.
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