WILLIAM Jefferson Clinton will arrive in Chicago just turned 50 and seeking four more years in the White House to leave his mark on American history.

His first four years have not been the stuff of history. He has backtracked on election promises, dithered on foreign affairs seen the Republicans win control of both Senate and House of Representatives, and tried to shrug off the Whitewater scandal when it threatened to envelop him and his wife, Hillary.

But he is a wiser, more mature man now and hoping that, come election day on November 5th the American people will give him the opportunity to develop into perhaps a great president.

He will have no more elections to face and will be able to concentrate on his vision for the America of the turn of the century.

Just this week he has set out this vision in his book Between Hope and History. The title is taken from a Seamus Heaney poem. The poet wrote it out for him by hand and the manuscript hangs in his office at the White House.

Clinton, former Oxford Rhodes scholar, now wants to go down in history as the thinking man's president. The books he says influence him include: the Meditations of the 1st-century Roman emperor Marcus Aurelius; The imitation of Christ, the Bible, "especially Proverbs and all the writings of St Paul"; Moral Man and Immoral Society by the theologian Reinhold Niebuhr, and Politics as a Vocation by Max Weber. ("It's a great call for humility".)

Being the first president to turn 50 in the White House since Theodore Roosevelt in 1908 has put Bill Clinton in a reflective mood. He notes that he now has "more yesterdays than tomorrows.

Some of the yesterdays he will want to forget. Two years ago he went through a dark night of the soul as the electorate passed judgment on his presidency by routing the Democrats and embracing Newt Gingrich's plan for a conservative state, a Contract with America".

For days and nights the President sat in the White House in a state of shock and denial, blaming everyone but himself.

Aides described the atmosphere as "bunker-like" as the President shouted at an adviser who had the courage to say that he had not taken strong enough stands, "Don't ever say that to me again."

Clinton insisted that he had taken courageous stands on such issues as the North American Free Trade Agreement and the budget deficit.

"The problem isn't that I haven't taken strong stands, it's that I don't have any help around here," he ranted, and accused his staff of treating him like a "f--ing pack mule and using my time poorly".

But out of the rages came a determination by the former Arkansas governor to survive, and not be a one-term president like the last Democrat incumbent, Jimmy Carter. Clinton turned to Dick Morris, the man who helped him win back the governorship which he lost in 1980.

Between them they worked out how to "reposition" Clinton, get away from the influence of an inexperienced staff, woo the middle-class voters who had deserted to the Republicans, and take his distance from the demoralised Democrats in Congress.

This was the famous "triangulation" policy whereby the President would be seen to be neither liberal nor conservative but somewhere above, rather than on, the classic political spectrum running from right to left. After all, Clinton had been elected as a "new Democrat", which was to combine being a liberal and a conservative.

Thus began the shift to the centre which has proved spectacularly successful and has seen Clinton's poll ratings surge ahead. He has unashamedly stolen Republican proposals on crime, budget deficit, welfare and family values, and left his opponents fuming.

But there are risks in a Democratic president lurching too far to the right. Clinton had promised in 1992 "to end welfare as we know it," referring to the federally funded aid system for poor families which critics claim only perpetuates their poverty.

But when Clinton overruled half his Cabinet and said he would sign the Republican welfare reform Bill which was rejected by influential liberal Democrats including Teddy Kennedy, Pat Moynihan and Chris Dodd, there was an outcry.

Here was a Democratic President abolishing the hallowed federal safety net for the poor dating back to Roosevelt and the New Deal. And penalising legal immigrants to boot.

DEMOCRATIC protesters heckled Clinton at his glitzy birthday celebrations last Sunday and there will be more protests in Chicago next week. But he can also point to his signing this week of the first rise in the minimum wage for years and the Bill to reform health insurance.

The important thing is that Clinton has prevented Bob Dole from using welfare reform as a "wedge" issue to win more middle-class votes. This is what the Dick Morris strategy is all about: win over middle-class swing voters.

On economic issues Clinton has an impressive record: 1O million new jobs, low inflation, low interest rates and a reducing budget deficit. Dole's 15 per cent across-the-board tax cut strikes even Republican commentators as irresponsible because it is likely to restart the $5 trillion public debt on an upward spiral.

But Clinton smells danger in the combination of Dole's 15 per cent cut and Jack Kemp's footballer charisma. Already the White House is dropping heavy hints of Clinton tax cuts to be announced in Chicago. Nothing as irresponsible as across-the-board, but something to help the average home without giving the rich a boost as well.

On foreign policy, the President cites his role in helping to broker peace agreements in the Middle Fast, Bosnia and Haiti.

Northern Ireland is also mentioned, but with less confidence since the IRA ceasefire ended.

His scapegoating of the United Nations over the Somalia disaster and the US attempt to oust Dr Boutros Boutros-Ghali from the top post is seen as a cynical retreat from earlier support for the organisation and the pledge that the US will pay its debts to the UN.

Then there is the "character" issue. Will Americans want to reelect a President whose second term, like that of Richard Nixon could end in disgrace, from a Whitewater rather than a Watergate?

And will the Special Prosecutor finally catch Hillary Clinton out over alleged false testimony?

The Gennifer Flowers affair and the first stirrings of Whitewater did not prevent Clinton getting elected in 1992. He and Hillary went on television to admit to what millions of other couples also experience problems in their marriage, And it worked.

The electorate knows he is not a saint. More people say they trust Bob Dole than Bill Clinton, but he is still ahead in the polls.

His new book, largely a compilation of his speeches, tries to portray Clinton the statesman and progressive thinker in the mould of Wood row Wilson and Theodore Roosevelt.

But it is too soon for the American people to grant him that status. Especially if they read another new book called Boy Chin ton in which a muckraking journalist, R. Emmet Tyrrell, regurgitates all the old dirt from Arkansas days and then adds some.

This is Clinton's problem. He wants to be loved, is filled with the best of intentions for his people but is unable to command their respect as he floats chameleon-like from one position to another. If they give him a second chance he may show that he is capable of greatness as well as political dexterity.