Can Irish republicans imagine a future without the Provisional IRA?

The hope in Whitehall is that the question of why Sinn Fein still needs a private army will become increasingly asked

The deep crisis that Tony Blair and Bertie Ahern confronted in Downing Street last night has been building for months. The republican involvement with Farc narcoterrorists in Colombia, the break-in at Castlereagh and the part played by non-renegade republicans in street violence over the summer had all increased the pressure on David Trimble to pull the plug on Northern Ireland's devolved institutions again. What changed with last Friday's raid at Stormont – and the discovery that republicans had been maintaining a live intelligence operation, including, apparently the targeting of prison officers – was that they, and not Mr Trimble, would take the blame.

So convenient was this that it has given rise to several conspiracy theories. The method of the raid on what is, after all, a parliament complex didn't help. Nor, to bend over backwards, does it follow that, because the IRA (which shows no sign of wanting a return to war) was continuing with intelligence gathering, it intended to use it in a murderous way. It's a safe bet that Mr Ahern last night asked some searching questions about the raid.

It remains likeliest that there wasn't some dark political purpose, devised on high, to the raid. But, in any case, this isn't really the point. The discoveries could hardly do other than send a shock wave through a Unionist population already disillusioned with the Good Friday Agreement. Which is why Mr Trimble is now pressing the Government to introduce an order excluding Sinn Fein from the executive, and says he had a promise in July that this would happen if there was further evidence of misbehaviour, to put it at its politest, by the republicans. It's a non-runner. It would require the support of the moderate nationalist SDLP – something the SDLP leader, Mark Durkan, made clear after meeting Mr Blair yesterday it wasn't going to get.

An alternative is the electoral route. Up to last Friday, and somewhat more tentatively since then, the Irish government has been suggesting that a better answer than suspension, and a hugely better one than a doomed attempt to exclude Sinn Fein, would be to let the Northern Ireland electorate have its say in fresh Assembly elections. Even more surprisingly, if from a different direction, Peter Mandelson, the former Secretary of State for Northern Ireland, also suggested yesterday that elections might be worth trying before the imposition of direct rule, though he coupled this with a call on republicans to bolster support for the agreement by taking a historic decision to declare the war over and stand down their army.

Barring some wholly unexpected initiative by the republican leadership when it meets Mr Blair today, this simply isn't going to happen. Mr Trimble was dismissive yesterday about what he called Mr Mandelson's "uncharacteristic wishful thinking", saying that this would see the SDLP "swallowed up" by Sinn Fein. He didn't mention the equally well justified fears about the parallel impact on his own party. For there is little doubt that the DUP would improve its showing. They could win the same number of seats as Mr Trimble's Ulster Unionist Party; given that the number of Ulster Unionist candidates supporting the agreement would be significantly fewer than last time, this would deliver an impregnable anti-agreement majority on the Unionist side.

It's true that some in the Irish government have taken the view that if those are realities, then they have to be confronted. The argument goes like this: perhaps Mr Trimble is too hemmed in to be saved; there is less chance of a meeting of minds while each party is adopting postures ahead of an election, and even if the result is as predicted, maybe the elements in the DUP that are somewhat more forward-looking than Mr Paisley would, once at the helm, finally agree to deal with Sinn Fein. In London, however this is as seen as prohibitively high risk, on the grounds that the prospects of such an accommodation, as long as Mr Paisley is around, are very thin.

Which appears to leave suspension – and probably the Irish government's reluctant assent to it – as the only course. The problem is that this takes place in much less favourable circumstances than what was hitherto the worst crisis for the agreement, the suspension of the institutions by Mr Mandelson in February 2000. That did, after a period of bitter recrimination by the republicans, allow the process to get back on track. But since then much, if not most, of the support for the agreement among Protestants, and the hope that went with it, has ebbed away.

There is a paradox about Mr Trimble's leadership. On the one hand, his pluralist vision, courage and resilience have been pivotal not only to the creation of the agreement but to its survival. And he repeated yesterday that he remained wholly committed to its success. On the other hand, one reason for the ebbing away of support for it, including in his own party, is that he hasn't articulated that vision in terms that resound so loudly among the Unionist population that they drown out the backward-looking tribalism of his rivals and tormentors. More than the repeated threat of resignations is needed to do that.

That said, it is now clear that the demilitarisation of republicanism has not kept up with the pace of their political progress: ministerial seats, release of prisoners, policing reform, now being amended in the interests of nationalists in a further bill, criminal justice reform and many other advances. While rejecting any idea of excluding Sinn Fein, Mr Durkan yesterday pointed out that republicans had hard questions to answer and that it was right to look forward to a "future without the IRA".

The hope in Whitehall is that during the breathing space afforded by suspension, the question of why Sinn Fein still has or needs a private army will become increasingly asked not only by Unionists but also by nationalists. Even more optimistically, some purport to see the fast growth of Sinn Fein's electoral support being checked and even reversed by the elections still planned for May unless they have shown real signs that they are ready eventually to disband the IRA.

That remains to be seen. While the outcome of the Friday's raid – in particular the prison officer lists – has horrified mainstream Unionism, the pictures of the unnecessary show of force with which it was carried out will stay long in the minds of nationalists. But Mr Trimble is entitled to wonder why he should be expected to form a government in Northern Ireland with Sinn Fein while it has not met the conditions that would allow Mr Ahern to do so in the republic. The implication of Mr Durkan's remarks is correct. In the new political climate, in which the republican leadership is evidently committed to the democratic process, Sinn Fein cannot for ever justify the continued existence of the IRA. So deep is the crisis that it's hard to see the democratic institutions being restored until republicanism shows some tangible recognition of that indisputable fact.

d.macintyre@independent.co.uk