But there is also no disguising satisfaction in government circles at an epochal event which ministers insist began with Mr Major's willingness to embark on the risky process which started with the Downing Street declaration last December. British officials could be talking openly with Sinn Fein before the end of November - and possibly significantly earlier - as a result of yesterday's historic announcement in Belfast.
The key text cited in Whitehall yesterday for what happens next is the letter sent on 7 April by Roderic Lyne, Mr Major's foreign affairs private secretary, to Gerry Adams, the Sinn Fein President.
The letter made clear that a preliminary 'dialogue' within three months would be about Sinn Fein's participation in political talks, about their further role in political life and about the 'practical consequences' of the end to violence. The third category includes the sensitive issue of the surrender of IRA arms.
One move which may not wait until then is the lifting of the Sinn Fein broadcasting ban. Sir Patrick and senior colleagues are known to want to end the ban, which they recognise has become counter-productive and exposes the British Government to derision and criticism. Ministers have been determined not to offer to lift the ban as 'bait' to the IRA, but if Mr Adams met the demand to take one extra step it might be ended swiftly.
Effectively the three months provide a quarantine period before Sinn Fein can be brought out of the political shadows. One senior official used the analogy of a 'decompression chamber: they go in as paramilitaries and come out as something akin to the other constitutional parties'.
There are other sensitive matters; the British Government has always ruled out an amnesty for republican prisoners. But officials have not in the past privately discounted the use of parole to release some IRA prisoners early.
Yesterday's announcement will certainly give fresh momentum to the search for a constitutional settlement, including an internal power-sharing assembly, joint cross- border boards covering areas like trade, tourism and agriculture, and changes to the Republic's constitition, which will enshrine the principle that a united Ireland can only come about with the consent of the Northern Ireland majority.
Negotiations under way between London and Dublin on a joint declaration are currently concentrating on how articles two and three II and III of the Irish constitution - which claim sovereignty over the North - could be modified and also how the British 1920 Government of Ireland Act might be changed in a symbolic balancing move.
James Molyneaux, leader of the Ulster Unionists, strongly expressed his extreme sensitivity about changes to the 1921 Act in his meeting with Mr Major yesterday. And changes to the 1920 Act - a detail but one regarded as highly important in Dublin - provided the only obvious legislative focus for a parliamentary rebellion by Ulster Unionists and hard-line Tory backbenchers. All the signs are that such a rebellion would fail.
Yesterday's historic turning point - or more accurately the Downing Street declaration - has been a traumatic event for what is, after all, the Conservative and Unionist Party. Quite a number of Tory backbenchers are uneasy about what they see as the Government's shift - in spite of its firm stand by the principle of consent - to neutrality on whether Northern Ireland's long-term future lies in the UK.
But Mr Major can count on massive support from the main Opposition parties; secondly the Tory unionist wing no longer has the quality of intellectual leadership furnished by the likes of Airey Neave, Enoch Powell, John Biggs Davidson and Ian Gow.
But most important of all, there is every ground for thinking that voters in Great Britain put rate an end to ending the conflict in Northern Ireland as a more important goal than Unionist doctrine.
If the hazards ahead can be overcome Mr Major's domestic and international reputation could rise rapidly. In those circumstances even the most hard-bitten anti-Major Tory backbenchers will think twice before before trying to rock the Tory boat.Reuse content