Kinnock blew it in 1986. Has Howard done the same?

Yesterday marked the day Howard's credibility was challenged by some in his own party

Tony Blair survived yesterday's debate on the Butler report relatively unscathed and can look forward to shutting up the parliamentary shop tomorrow. Michael Howard was right to lead the opposition attack, if for no other reason than that he forced the Prime Minister to give some account of why he misled - albeit in good faith - a number of his own Labour MPs into supporting the Iraq war.

Tony Blair survived yesterday's debate on the Butler report relatively unscathed and can look forward to shutting up the parliamentary shop tomorrow. Michael Howard was right to lead the opposition attack, if for no other reason than that he forced the Prime Minister to give some account of why he misled - albeit in good faith - a number of his own Labour MPs into supporting the Iraq war.

Unfortunately Mr Howard was hobbled by Mr Blair's charge of "shabby opportunism" in pressing home his legitimate attack. But there will never be any runs scored on Iraq by the Tories unless they say, unequivocally, that they regret not only voting for the resolution authorising war but also for supporting the war itself. Mr Howard rightly said that Mr Blair's credibility is on the line. I fear that yesterday also marked the day when Mr Howard's credibility as Tory leader was first challenged by some in his own party - not least by Sir Patrick Cormack in an incisive intervention.

The seven-year itch has again cast its spell on British politics. We have been here before - in 1986 - seven years after the Tory victory of 1979. The Westland crisis cannot, of course, be compared with the Iraq war. But the subsequent consequences were extraordinarily similar to today's circumstances. The immediate political cost to the Thatcher government was the loss of two cabinet ministers. This was followed by internal convulsions at the heart of government that momentarily led to a loss of nerve by the Prime Minister who wondered whether she could even continue in office. But for the incompetence and verbosity of the Leader of the Opposition's Commons performance in a crucial debate, the day might have ended with Margaret Thatcher's resignation.

A few months later, in the summer, the governing party had to defend two by-elections. In one case the sitting member died and the seat was lost to the SDP/Liberal Alliance. In the other seat the MP resigned to seek an alternative career in the media - but the governing party narrowly held off the Alliance challenge by 100 votes. The real political story, however, was the inability of the main opposition party to make any electoral progress. Labour came third in both by-elections. Re-energised, the governing party prepared for the autumn party conference season with a blizzard of policy announcements under the banner "The Next Moves Forward". The following June, Thatcher was safely back for a third term.

Overshadowing the run up to that general election was the nightmare of a property re-valuation which threatened to inflict arbitrary punishment on hapless householders whose properties were rising in value thanks to the Nigel Lawson boom. So to avoid a backlash against the old rating system, the community charge emerged. The implications of yesterday's announcement of the Government's review of the council tax system, despite the Local Government minister Nick Raynsford's bland reassurances, looks like a potential recipe for a repeat of the 1980s poll tax debacle.

The crucial difference, however, between then and now is the performance of the Liberal Democrats. Try as they might, however successful at by-elections, the SDP/Liberal Alliance could not break the mould of the two party system. Last week's by-elections, set alongside Brent East last September and the consistent run of opinion polls, provides the most tangible evidence yet that Britain is on the brink of a three-party system.

In the short term this should certainly send a shiver down the spine of Michael Howard. The latest ICM poll puts the Tories, at 30 per cent, a mere 5 points ahead of the Liberal Democrats. Worse, Labour are now 5 points ahead of the Tories.

But before Tories succumb to the temptation of more introspection and infighting, they can reflect on one comforting fact. Labour has lost roughly a quarter of its support since the 1997 general election. There are now three political battles being fought out across Britain that will change the way future general elections will be fought.

First there will continue to be the traditional Labour-Tory fights. But the Lib Dem-Tory and Lib Dem-Labour contests will be as important to the future direction of British politics. And in the marginal Labour seats that were won from the Tories in 1997, any slippage in the Labour vote - perhaps due to the Iraq war - to the Liberal Democrats can gain the Tories a number of extra seats.

Sometimes political parties are just unlucky. But the Tories should be encouraged that on health, education, law and order and administrative waste, it is their beliefs that drive this Labour Government. It is, of course, cold electoral comfort that, tactically, they have been outwitted. The whispering against Mr Howard has begun; however, his leadership is not (yet) the Tories' problem. It is the failure of some of their candidates to realise the extent to which hard graft on the knocker, in all weathers and throughout the summer, when Labour MPs are on holiday, can make a difference.

mrbrown@pimlico.freeserve.co.uk