He feels it, I'm told, but he showed little sense of drama at his Downing Street press conference yesterday, seeming as bland and almost surreally calm as usual. With the Irish premier, he stuck by the convenient pretence that the peace process was unaffected by the IRA's resumed murder campaign. In John Bruton's words, "our timetable has neither been advanced nor accelerated by the intrusion of violence". Sinn Fein and the IRA were, they implied, some kind of side-issue.
This is forgivable. Democratic leaders want to give the impression that they are not swayed by violence. They may even need to believe it themselves. But in this case it is hooey. The frantic activity of recent days was almost self-evidently the result of the end of the IRA ceasefire. Before, there was lull. After, there was flurry. Yesterday's date for all-party talks was intended to beckon the ceasefire back.
If it does, the hurtle of negotiations and elections planned for the next few days may mean something. The 10 days of consultations between the governments and the Northern Ireland parties about peace elections, referenda and all-party talks will - everyone seems to think - end without agreement. London and Dublin would then have to impose the next stage. It's likely that they have agreed that the electoral system will be proportional representation for a single Northern Ireland poll, helping the smaller parties; and that they intend to hold referenda.
In the North, the question may be based on paragraph 10 of the original Downing Street declaration, affirming the right of all parties "which establish a commitment to exclusively peaceful methods'' to discuss the future of the province.
Even that would only take everyone back to the problem of decommissioning arms. Instead of it being a precondition for talks - the British demand that Republicans described as stalling - it would become the first item on the agenda of those talks. It is as if a white line has been carefully erased from the beginning of a running-track and repainted a few inches further on.
So even now, not one of the really serious questions has been addressed; not the actual decommissioning of weapons; nor any possible future assembly to rule Northern Ireland; nor the punishment beatings and Sinn Fein's total renunciation of violence; nor relations with the South; nor the IRA's willingness to stop killing without a clear path to a united Ireland.
Since the return of the bombing, the suspicion has revived in London that, as soon as these big questions are addressed, it will become clear that the answers are unacceptable to one or other important group; and the future will darken.
But who knows? This endlessly slow weaving towards those questions has been valuable in its own right, buying time and saving life. In political terms, this has truly been the peace that passeth all understanding, but it has been a lot better than what preceded it. While there's waffle, there's hope.
For Major, the return of hope would be of huge psychological importance. Without the Irish peace process, his administration would lack a central purpose and its chances of surviving this year would be diminished. Wobbly backbenchers would lose heart. Political decay would spread the faster.
The next couple of months are not, of course, devoid of risks of other kinds. This programme of talks and deadlines offers many opportunities for a breakdown of trust between Unionist politicians and Downing Street. We saw a glimpse of that this week, when ministerial briefing about the deal allegedly offered by the Official Unionists over the Scott vote infuriated David Trimble and helped propel his party into the Opposition lobby.
Trimble seems to have put that episode behind him; but Major could not risk many more like it. A chill ought to have spread up ministerial spines at the words of John Taylor, Mr Trimble's deputy, who said on Tuesday night that the Government was collapsing and "is in its dying months".
Even now, most senior Tory and Labour people I speak to think the opposite: that Major will be able to go the full distance. There is even talk of 1 May 1997 being the likely date for the election, because it comes a few weeks after voters see the effects of a November Budget on their pay- slips, and a similar time before the final deadline of the 1992 Parliament.
Some readers will ask how politicians can think this way, after the cliff- hanger vote on the Scott report, defecting Tory MPs, the poor quality of ministers and the lack of important legislation. Doesn't the reek of decay hang over Westminster?
The answer is that the calculating MPs are hard-headed tacticians, not commentators or moralists. They assume that the Ulster Unionists will continue to back Major in confidence motions. Why? Because just now, while the Commons is almost equally divided between Tory and Opposition, the men of Ulster have special leverage. But elections tend to produce clear Commons majorities; why, therefore, would the Unionists throw away their rare parliamentary power?
This still seems to me a plausible argument; cold Ulster self-interest is a powerful reason for expecting a late election. But it is not an iron law. If the Tories crumble some more, the Unionists may conclude that a Labour government is inevitable, and that it would be better to be on good terms with it, as the parliamentary executioners of the Major administration, than to resist its coming.
Labour's Northern Ireland front-bencher, Mo Mowlem, has greatly impressed Unionist MPs, including John Taylor. And Labour's decision to abstain on the annual renewal of the Prevention of Terrorism Act (not an easy decision, after so many years opposing it, and one which may well split the party in the lobbies) removes a long-standing Unionist grievance. New Labour, new friends?
It doesn't mean that we should all move to election alert. The Tories, and their leader, have remarkable powers of resilience. Across the country there are signs that their core vote is beginning to firm up again. They are getting ready for a ferocious by-election at Tamworth, a seat they believe they may hold, thus ending Labour's long run of successes and - perhaps - turning the tide. In Conservative Central Office, the view is that "if only people start to think we can win the election, then we'll start moving again, and anything becomes possible".
But getting there needs time. It hinges on this fragile, ageing Commons majority and this fragile, late-in-the-day attempt to rescue the Irish peace process. Major's greatest daily weakness and his only historic project have become inextricably interlinked. And he knows that if he stumbles again, Labour is waiting.