The governing coalition in Pakistan says it is close to an agreement to impeach President Musharraf. He planned to attend the opening ceremony of the Beijing Olympics this week. The Foreign Ministry has issued conflicting statements about whether the trip will go ahead. It appears that Mr Musharraf will go, a day later than originally planned. The prospect of impeachment has clearly exercised his mind. There are precedents for political leaders to be deposed while attending international events.

The danse macabre between Mr Musharraf and the ruling alliance requires speedy resolution. The most dangerous source of instability from Islamist militancy threatens now to be an increasingly unstable Pakistan. Political leadership in that nation is far from adequate to meet the gravity of the threat. Persisting with the internecine dispute will discredit constitutional politics. At the extreme, it may even lay the foundation for another military coup.

Mr Musharraf's authority has been rapidly eroding, and for good reason. His sacking of senior judges last November was an affront to the principles of constitutionalism, and has overwhelmed all other issues in Pakistani politics. He stood down as head of the armed forces at the end of last year, belatedly and with scant appreciation of the costs to his authority by combining military and civic roles in defiance of the Constitution. Popular discontent has burgeoned as soaring food prices squeeze the living standards of the poor.

This is a breeding ground for Islamist extremism; and Mr Musharraf has become a liability in the struggle to defeat it. He deserved credit for allying with the West after 9/11 and rejecting the Taleban. But in return for aid, debt relief and a softening of the perception of Pakistan as a terrorist-supporting state, he has delivered only limited successes in police operations against Islamist cells. Most lamentable, military operations against the Taleban have been undermined by Mr Musharraf's willingness in effect to give up territory in return for what purport to be peace settlements agreed with tribal militants. It would serve Pakistan's interests if Mr Musharraf anticipated the moves to impeach him, and left office voluntarily and promptly. But if Mr Musharraf's position is untenable, that of the governing alliance is scarcely more creditable. The Pakistan People's Party and the Pakistan Muslim League have been locked in dispute over the short-term issues of impeachment and the judiciary. There are many fundamental issues affecting Pakistan's future that are being neglected in these squabbles.

Pakistan must become a reliable ally in combating the Taleban. It needs to interdict domestic sources of terrorism and not only transplanted foreign Islamist cells. The nuclear proliferation that occurred under Mr Musharraf's rule may yet allow the awful possibility of a bomb under the control of religious extremists. Ominously, the Inter-Services Intelligence (ISI) agency, which is widely suspected of links with Islamists, has successfully repulsed an attempt to bring it under civilian control.

Pakistan's transition from martial law to stable constitutional government is at an impasse. Something must give. That something should be Mr Musharraf.