It a matter of dispute how crucial his defence of the constitution was in 1992. Some research suggests he did little more than provide for floating electors the excuse they needed not to vote for Neil Kinnock. But the issue made a passionate advocate out of Major; he was comfortable with it and it energised his campaign as perhaps no other had. And it may be that - at least about Scottish and Welsh devolution - the voters subconsciously, and correctly, detected that Kinnock's heart wasn't in it (it still isn't).
Mr Major's speech will emphasise the centrality of the Westminster parliament, trailing some reforms to improve the timetable for, and scrutiny of, legislation in the Commons. The implication will be that there is nothing a Scottish Parliament or a Welsh assembly can do that an evolving Westminster one could not do better.
Tony Blair is committed to devolution though he personally shares some of Kinnock's reservations; and it certainly isn't the overriding priority it was for John Smith. He is also determined to find workable answers to the objections that behind the scenes, for several months now, he has been pressing his Scottish colleagues to confront.
Blair is determine to maximise consent for home rule on both sides of the border. As a party leader who has converted his party away from tax- and-spend, he isn't (and can't be) wholly comfortable with the leeway a Scottish Parliament will have to raise additional taxes of up to 3p in the pound. And unlike many home rulers, he doesn't dismiss outright the West Lothian Question famously raised, again and again, by Tam Dalyell during the fateful passage of the Scotland Bill in 1977-78.
If Scottish issues were to be decided in an Edinburgh Parliament, what right would Scottish MPs have to debate and vote in the House of Commons on legislation that concerned only England and Wales? Or, as Balfour asked about similar proposals, in 1914, "Are you going to leave the whole of these 72 Scottish members here to manage English education?
Blair is almost certainly conscious that one trick the Tories are planning is to make a combination of the two problems - tax powers and the West Lothian question - converge on the single figure of Gordon Brown, the Shadow Chancellor. What right, they will ask, has Mr Brown, a Scottish MP, to fix as Chancellor tax levels for England and Wales which may not be, because of the Scottish Parliament's tax-raising powers, the final rates for his own constituents in Dunfermline East?
All of which helps to explain why Blair is now doing some hard thinking ahead of publication of Labour's Road to the Manifesto on Thursday week. So far Labour has argued determinedly that the tax-raising powers are much less threatening than they first appear, making the point that these powers might never be used. In the words of a report from the independent Constitution Unit, published today: "The difficulty of raising direct taxation in an environment where there will always be an election in the offing, either in the UK or in Scotland, should not be underestimated." But there was a marked silence from Labour's rebuttal-prone media spokesmen when the Scotsman reported last month that Mr Blair was coming under pressure from his own ranks to shelve the tax-raising powers. I would not now be in the least surprised if Mr Blair goes into the next election pledging that the Scottish Parliament will not have tax powers, at least during a first Labour term.
On the West Lothian question and the related question of whether the relative over-representation of Scottish MPs at Westminster should be curbed by reducing their number from 72 to 59, the answer is less clear. One possibility is to preclude Scottish MPs from voting on English-only business. Contrary to most Labour mythology, this would not necessarily leave a Tory majority in charge of English business, since, as the report points out, whenever Labour has had a convincing majority in the UK, it had had a majority of English MPs, too. But whether Mr Blair goes down that route or another, he is determined to come up with some kind of answer.
The third aspect that, it is safe to assume, is currently absorbing Mr Blair concerns whether Labour's plan will require a referendum in Scotland. The assumption so far has been that the general election will be enough of a mandate. But both the left think-tank, the Institute for Public Policy Research and, more guardedly, today's Constitution Unit report suggest that a referendum could go a long way towards entrenching public support for, and understanding of, the Scottish Parliament. This will be heresy to some Labour Scots, of course, who are convinced it isn't necessary: but if it isn't, what is there to fear?
The anti-home-rule Dalyell will try to whip up Labour support for the referendum clause that will certainly be tabled by the Tories if Labour's Bill doesn't include one. More importantly, with Labour committed to a referendum on change in the electoral system, and quasi-committed to one in the event of a decision to join a single currency, can it really sustain the argument against holding one for the biggest change in the history of the Union - especially when Blair is confident that a referendum would be won by the home rulers?
Blair is said to believe that every attempted home rule measure in the past has foundered either because it was too ambitious, or because it was not seen to command full consent, or both. He is determined to see this one work. This may mean confronting Scottish Labour MPs with some hard choices. But he will at least have allies among those impatient activists who do not want to see the impact of the first Labour government for 17 years on the fabric of ordinary life in Britain lost in the legislative quagmire that will threaten a Scotland Bill which can't be passed or made to work.Reuse content