Leading article: A historic bargain is still in prospect

Tony Blair's decision to forsake the blue skies of Miami for the swirling grey mists of the Irish peace process can be seen as an effort to head off a looming problem rather than an admission of full-blown crisis. After many months of effort devoted to cantilevering Sinn Fein and Ian Paisley's Democratic Unionists into a new coalition government, yet another snag has developed on the vexed question of policing.

The goal is to reach an understanding between the republicans and the unionists so that an election can be held on 7 March. That will elect a fresh Belfast Assembly in which the two opposing traditions can share power. To get to that point, Gerry Adams was supposed to call a historic party meeting at which Sinn Fein would commit itself to co-operating with the police and all criminal justice institutions.

Mr Adams has done so, announcing that the meeting will take place some time this month. Mr Paisley was then supposed to indicate that he would share power. The Government, for its part, was to announce that policing and justice powers could be transferred to Belfast by May 2008. Mr Paisley would undertake not to obstruct this transfer, as some members of his party have threatened to do. In a recent statement, he has in fact acknowledged that Sinn Fein is making positive moves, but he did not include any promise not to hold back on the transfer of policing powers. It is this omission which is exercising both the Prime Minister and republicans, and it is not difficult to see why.

Quite a few in the Sinn Fein and IRA grassroots find, after all those centuries of republican rebellion, that the idea of solemnly undertaking to support the police sticks in their craw. There have been complaints that Sinn Fein has threateningly ordered potential dissidents to stay away from public meetings on policing, while a number of the current Sinn Fein Assembly members look likely to part company with the party on the issue. Given the sensitivities of the moment, Sinn Fein wants to extract as much Paisleyite clarity as possible to reassure the doubters in its ranks.

By the same token, Mr Paisley's lack of lucidity in ruling out delaying tactics may well spring from his own problems with the loyalist grassroots. Some of these do not want power-sharing yet; some do not want it ever. Like the republicans, Mr Paisley is gearing up for a historic deal, and like them he wants to keep any split in his ranks as small as possible.

For a year or more the peace process has proceeded at a quite leisurely pace, with the key parties being given months to absorb the new political facts of life and several ostensibly unbudgeable deadlines passing without calamity or penalty. But now there is a new sense of urgency, since almost all elements in the peace process want that March election and know that its postponement would seriously upset the overall timetable.

There is therefore a new political tension in the air, since making the breakthrough to a new bout of devolution will require both Mr Adams and Mr Paisley to face down their respective fundamentalists. It will also require additional flexibility on the part of both towards their opponents, since the absence of trust has been a constant problem in conducting political business.

And yet there is heart to be taken even at this tricky point. For years, many wondered whether the republicans were serious about doing non-violent business; more recently the question has been whether Mr Paisley was genuinely interested in a deal. Now the problem is not one of sincerity, but rather of internal management. For although some backwoodsmen are unhappy, there is now a definite sense that the two leaderships are working towards a historic bargain.