The sacking of Gen Stanley McChrystal by US President Barack Obama last week has sparked both fears and possibilities for various players in the Afghan conflict.

Image caption Gen Petraeus has warned of an escalation of violence in Afghanistan

Before his successor, Gen David Petraeus, settles in his job, the Americans may feel compelled to make an assessment of why their "big push" in Helmand province is seen by many to have failed and the one in Kandahar has so far not materialised.

Any revised US strategy would inevitably make demands on both the Afghan government and the Pakistani military.

Afghan President Hamid Karzai appears to be already focusing on broader reconciliation, including talks with the Taliban.

In June, a peace conference he convened in Kabul recommended the removal of Taliban leaders from a UN blacklist and the release of Taliban fighters from prisons to pave the way for such talks.

Confusing signals

For Pakistan, analysts say, it means yet another opportunity to create realities on the ground that Gen Petraeus would find hard to ignore.

Image caption Elements within Pakistan's intelligence are said to be "working" with Islamists

Pakistani intelligence officials have been recently leaking information to the press suggesting that Pakistan is brokering talks between President Karzai and the Haqqani group, a long-time protege of Pakistan's ISI intelligence service.

But just four months ago, the Pakistanis arrested one of their favourite guests and a top Taliban commander, Mullah Baradar, for reportedly talking to the Karzai government behind their back.

These are confusing signals, indicative of Pakistan's murky geostrategic problem-solving mechanisms.

Pakistan is a narrow strip of land - in some places just over 300 miles (483km) across - and feels vulnerable against its much larger eastern neighbour India, with whom it has fought two wars over the disputed region of Kashmir.

To the west, it has a long and disputed border with Afghanistan, a traditional ally of India.

The domination of the military establishment in Pakistani politics prevented the country from exploring diplomatic solutions to these issues.

In 1980s, an international coalition led by the US funded an ISI programme to raise Islamist militant groups to fight the Soviet troops in Afghanistan.

These groups, and after them the Taliban, inherited Afghanistan.

Under them, Pakistan was able to keep Indian influence in Afghanistan under check for nearly two decades.

This period also gave a boost to the Pakistani idea of ensuring "strategic depth" in Afghanistan against a possible Indian invasion.

After the Soviet withdrawal in 1988, the ISI also used these groups to spark an insurgency in the Indian-administered Kashmir.

When the September 2001 attacks took place, Pakistan was faced with the impossible task of protecting these groups while at the same time siding with the international alliance against al-Qaeda and the Taliban.

This has been achieved at considerable cost to the country.

'Calculated' ambiguity

Elements within the Pakistani intelligence services are widely suspected of "working" with the very militant groups that are involved in killing thousands of Pakistanis - both military and civilian.

The riddle that the Americans and the rest of the Western powers now need to solve is how to persuade Pakistan to deliver in Afghanistan without putting a gun to its own head Ilyas Khan

Reliable witnesses in Waziristan say in recent months they have seen truckloads of armed Punjabi Taliban - known for their spectacular attacks on Pakistani military targets - pass through dozens of security checkpoints every day to reach the border towns.

They claim having seen both Punjabi and local militants using military transport to move in the border areas.

But the policy of turning these militant sanctuaries into no-go areas for civilian government, journalists and other civilian observers has cast a pall of doubt on the activities there.

"What we have to always figure out with Pakistan is: are they working with the Taliban to support the Taliban or to recruit sources in the Taliban?" Gen Petraeus stated during his confirmation hearing before a panel of the US senate on Tuesday.

Many believe this "calculated" ambiguity has repeatedly helped the Pakistani military to buy time and demand money from its Western allies without delivering results in the Afghan conflict.

But this has also sapped the strength of the Pakistani state.

The concept of institutional accountability has lost its meaning, public governance has become chaotic, the economy has gone haywire and political alienation has taken hold of nearly the entire country.

Exacting any further domestic price for strategic aims is becoming perilous at a time when the Americans have already laid down a roadmap for their Afghan operations and must enact an exit plan that ensures the elimination of the al-Qaeda threat.

Many quarters in Pakistan express the fear that this could descend into a dangerous game.

These quarters suspect that recent leaks of a Pakistan-backed reconciliation in Afghanistan may be yet another Pakistani ploy to confuse the situation.

They believe that any power-sharing deal in Afghanistan in which pro-Pakistan forces do not have the last word does not fit in with its objectives.

The riddle that the Americans and the rest of the Western powers now need to solve is how to persuade Pakistan to deliver in Afghanistan without putting a gun to its own head.