Pakistan treated General David Petraeus to a full-costume preview of the breakdown of every part of its society yesterday. Thousands of lawyers and journalists took to the streets to protest against the refusal of President Zardari to restore top judges. At the same time, Zardari is in urgent talks with Saudi Arabia to raise cash so that he can avoid turning to the International Monetary Fund, with its awkward demands for reform. The border with Afghanistan is also in turmoil after an airstrike on Friday, reported to be from a US unmanned aircraft in Pakistan’s airspace.

The reassuring feature of Pakistan has always been that extremism has been peripheral, and that government has worked, sort of. But we are now seeing a glimpse of what disintegration would look like. The threat that Pakistan will move towards extremism should be top of the new US president’s list of fears abroad. It could mean the defeat of even the reduced aims that the US and Nato still hold for Afghanistan. Pakistan itself could present a far worse problem than its neighbour – nuclear-armed, and with more than five times as many people.

John McCain has said little on Pakistan. Barack Obama’s best-known remark on the subject, early in his campaign, was his support for US aerial bombing, a remark that unsurprisingly enraged Pakistanis. But his latest comments, a few days ago, are more thoughtful, and important. He has suggested throwing US energy into an India-Pakistan deal over Kashmir. That is at least as valuable a target as Israeli-Palestinian talks, and given the recent grudging truce between Delhi and Islamabad, one with some chance of progress.

That will have to wait until the result of the American election. Yesterday it was General Petraeus, as an early visitor, who was hit with all the tests of pessimism that Pakistan can devise. His reputation as a professional optimist is due to the “surge” in Iraq, which he oversaw. There is an extra frisson about his views because of speculation that he might one day jump from military to politics; some have talked of him as a possible presidential contender. He took over as head of US Central Command four days ago, and so will have charge of the US’s fighting in Iraq and Afghanistan under the new President.

Zardari told him that Pakistan’s tolerance for US airstrikes had run out. The language, talking of “frustration”, was something short of an ultimatum. Zardari, in his few months in office, has made clear his support for the US. The US’s pursuit of some of the al-Qaeda supporters and Pakistan Taleban may also be helpful to Pakistan’s Government, blunting its expressions of outrage. But the strikes risk damaging the US cause, and Pakistan’s stability. For seven years Pakistan’s leaders have been involved in intricate calculations about how much to tolerate or help US military action. It is now clear that the strikes are enormously inflaming extremist sentiments. All that the US offers is unproven claims that it has caught or hit many militants.

One of the first decisions to confront the new US president will be whether to continue with this policy. It cannot seem sensible to do so. Instead, the US needs to make an energetic effort to help Pakistan to solve its huge array of other problems.

The first is financial. Zardari’s attempt to dodge the IMF with the help of Saudi Arabia will only postpone the reforms that Pakistan needs to make. No mystery why. Most reforms would be unpopular, and would weaken Zardari’s shaky grip on power.

He has dodged, so far, the question of the judges, sacked by his predecessor President Musharraf. His motive is again clear; the Chief Justice, Iftikhar Chaudhry, would be likely to question the legitimacy of the amnesty against corruption charges that Musharraf gave Zardari. If Chaudhry got back in, Zardari could be out. But while the judges remain on the sidelines, they are a focus for the antiZardari movement. That now includes the Pakistan Muslim League, which resigned from Zardari’s Government, but which still runs the Punjab, the most powerful province. Nor does the Army much like Zardari. And nor do many ordinary Pakistanis. Polls suggest they were prepared to vote him in on a wave of sympathy after the assassination of Benazir Bhutto, his wife. But they don’t love him and may not vote for him again.

No money, not much support; these are the shaky foundations of the Zardari Government. It is hard to see it lasting. The US should not repeat the mistake of the past eight years and back a President of Pakistan who supports America regardless of how he runs his country. It should urge Zardari, and his potential successors, to tackle Pakistan’s problems, not dodge them. That means the IMF, and judges, and even Kashmir.

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