One day, Labour will need the Liberal Democrats

'Such is the ambiguity of Tony Blair disclosed by Ashdown that we still aren't certain what he was up to'

In an age of instant historiography, Paddy Ashdown's forthcoming volume of diaries is an important, and in a favourable sense, old fashioned political book. It wasn't written primarily for sensational serialisation but to be a historical record. Unlike Dick Crossman, Barbara Castle and Tony Benn, Paddy Ashdown did not sit around the Cabinet table. Indeed, a good deal of the most interesting material in the book looks like being precisely about why he didn't. But like those other political diarists, he has brought us, thanks to contemporarily written narrative, into the heart of politics because of the intimacy of his dealings with the first Labour Prime Minister for more than 18 years.

In an age of instant historiography, Paddy Ashdown's forthcoming volume of diaries is an important, and in a favourable sense, old fashioned political book. It wasn't written primarily for sensational serialisation but to be a historical record. Unlike Dick Crossman, Barbara Castle and Tony Benn, Paddy Ashdown did not sit around the Cabinet table. Indeed, a good deal of the most interesting material in the book looks like being precisely about why he didn't. But like those other political diarists, he has brought us, thanks to contemporarily written narrative, into the heart of politics because of the intimacy of his dealings with the first Labour Prime Minister for more than 18 years.

The most arresting part of the account, of course, is how close Tony Blair appears to have come to bringing a minority of Liberal Democrats into a coalition without needing to. Here, as Ashdown's account confirms, were two men not rooted in their own party tribes, who liked each other, who could not really understand why two parties which had so much in common should be fighting rather than co-operating. Nor would it have been that difficult.

Ashdown always made it clear to Mr Blair in the run-up to the election that the Liberal Democrats would need more than a handful of mere Cabinet posts. There would have to be a common programme to demonstrate that the new Lib Dem ministers were not merely there robotically to carry out a Labour programme. The elements of that common programme were none too testing for Labour.

The best information suggests that the items they were hoping for was a personal commitment by Mr Blair to back electoral reform in a future referendum, universal nursery education, agreement of Labour to drop the second question in its planned referendum on Scottish devolution, and an independent Bank of England. It even looks as if Mr Ashdown would have settled for less than all four. And since Gordon Brown was already planning to make the Bank independent, the vote to allow the Scottish Parliament tax raising powers would anyway be a resounding yes, and universal nursery education became Labour policy, these were hardly insuperable hurdles.

So why, again, didn't it happen? Originally it merely seemed as if the Labour majority was too big. First Mr Blair didn't need the third party, as he might have done, to offset a hard-left rump who might otherwise have held the balance of power in the Commons. And second, it might have seemed all the greater offence to his own, triumphant, party if Mr Blair had offered members of another party posts in government.

Again, more recent information suggests it wasn't quite that simple. For not that long before the election, Mr Blair seems to have remarked to Mr Ashdown in one of their many conversations that actually a large majority might not be unhelpful to doing what Mr Ashdown in particularly liked to call "the big thing" - ie coalition - because it would give him greater freedom. Which was, of course, right. For 1 to 2 May 1997 was a revolutionary moment in British political history. Given that the election victory was above all a personal triumph for Mr Blair he could have done almost anything; and he could have changed essentially tribal perceptions for good by justifying his action on the grounds that his new government would represent not a minority of the electorate - just over 43 per cent - but a true majority of the electorate: just over 60 per cent.

So why in those last hours before and immediately after the general election didn't it happen? I suspect Mr Ashdown's book, will not, in the end, provide the complete answer to this question. There were actually two moments when the Rubicon might have been crossed.

One was much earlier, back in 1996, when the two parties might have made an explicit agreement to fight the election as prospective coalition partners. And the second was in the last heady hours before the plug was pulled on any such idea on the Friday after polling day.

The diary makes clear, if such clarity was still needed, the enormous influence wielded by Mr Brown. And while a fascinating passage makes clear Mr Brown's recognition of the extent to which the then future Chancellor was pursuing traditional Liberal goals of individual fulfilment, enterprise and real competition, the diary also makes clear how wary he was of proportional representation. Likewise, no doubt, John Prescott. Indeed, one of the abiding senses one gets from the diaries is the extent to which Mr Blair was isolated. Robin Cook was strongly in favour of PR, with all the possible consequences, not least because he correctly saw that it would enfranchise much of the core Labour vote. But Peter Mandelson, active a part though he played in contacts with the Lib Dems, did so partly from the tribalist motive, of "hooovering" up Lib Dem support.

So what does all this mean for the here and now? Such is the ambiguity of Mr Blair disclosed by Mr Ashdown that we still can't be certain what he's been up to. Was he just stringing Mr Ashdown along or did - and does he still - want, ideally, to do "the big thing"? When he announced to Mr Ashdown on the day after polling day that instead of coalition he was going to pick up Mr Ashdown's own Stanley Baldwin-derived alternative of an inter-party Cabinet committee, he made it clear he was still determined to end the schism within the British left which had delivered a Conservative century, adding - remarkably - that in the long run this could mean merger between Labour and the Lib Dems. Did this mean a mere Labour takeover, or did it mean a true rebirth of the 19th - and early 20th century - Liberal Party? Mr Ashdown - almost certainly correctly - thinks Mr Blair was sincere. But if he wasn't stringing the Lib Dems along he was also - strangely for the decisive warrior of Kosovo - fairly indecisive when it came to the crunch.

But - and here's the most important point - the fact that Mr Blair - and to be fair to some extent Mr Ashdown - may have pulled back at what was certainly the best moment for coalition-making from a position of strength, that doesn't mean the story is all over. You may lament that a coalition government would have been more pro-European, and more liberal. But that's old news. What it does mean is that if it is now to happen it will happen because of the electoral arithmetic.

But if that's to happen, it means more than merely waiting around for a hung parliament. The left can't plan for hung parliaments because in any condition in which they might occur, a Tory victory is more likely. So the fact remains, as Mr Ashdown far-sightedly always saw - that the way has to be prepared first. And for this, as his book will no doubt make clear, a lot of the work has already been done. There is, too, as Mr Ashdown neatly put it yesterday, two "scale models" already in operation in the Welsh assembly and the Scottish parliament. It isn't a grand, noble plan, any more. But it could yet be expedient. And as electoral destruction looms, whether in the next parliament or in one after that, it's still workable - if the Lib Dem or Labour leadership at that time are ready to make it happen.

* d.macintyre@independent.co.uk