Cartoonists and photo librarians are already printing their farewell selections on George W Bush, and the Guardian's G2 has been giving him one last bashing or three – though the famous US presidential transition means Dubya still has three months to serve.

But how bad a president has he been in the larger scheme of things? Who was the worst and indeed the best of the 43 elected since that remarkable constitution (unlike the EU's wordy jargon, it can be both read and understood in 20 minutes) was painstakingly constructed at Philadelphia in 1787?

My views of the No 1 are pretty conventional, I'm afraid. I'm an Abraham Lincoln (1861-65) man, though George Washington (1789-97), wise and unflashy founding president of the republic, commands a good case. Eight years is enough for anyone, he realised, an enduring precedent, which even Vladimir Putin had to respect (sort of).

Up there too is the man who breached it in exceptional circumstances: Franklin D Roosevelt (1933-45). He never gets enough credit, says me, for being the greatest political figure of the 20th century, the leader who mastered both the depression and global war against fearsome enemies without resort to tyranny or barbarism.

But we can all play this game. As with sporting heroes, great movies and much else there are people who devote huge amounts of time to "best of'' lists, as any Google search confirms. What I call Wikipedia University confirms that my trio usually takes the top three places, with Thomas Jefferson and Theodore Roosevelt – he wouldn't have cut those Wall St bankers so much slack – just behind them. That's cool with me too.

Here's another I found easily, one which includes useful summaries of achievement and stirring quotes. JFK (1961-63) doesn't make the top 10, nor should he, but the compiler includes him as a "personal favourite". That's nice, but it's also a warning that – as with movies where recent duds often outshine enduring classics – we can all be misled by our own perspective.

The Times – London, not New York - took a crack at this one the other day. A panel of Times pundits ranked all 42 (not 43 because Grover Cleveland got elected for two separate terms) with what I thought were some perverse results, especially in the back half.

As Times posters were quick to protest, you can't put Richard Nixon (1969-74) at No 37. Yes, he was a seriously flawed man, paranoid and vengeful (a US chum says McCain would be the same), and driven from office for shocking misconduct, the only such president.

But he was also a brilliant man who drew isolated China back into the international sphere and ended the Vietnam war. That had been messed up by Lyndon Johnson (1963-69) who makes the cut at No 12 for his domestic achievements, anti-poverty programmes, but above all the civil rights legislation, which has allowed Barack Obama to be where he is today.

In doing so Johnson, the supreme political manipulator, admitted that the Democrats would "lose the south for a generation". True, though they may be about to get them back. But Johnson too was a flawed political genius for whom Bill Shakespeare would have got out his Olivetti, as he would for Nixon but few others among the 41-plus-Grover-and Grover. Most were fairly unremarkable men upon whom varying degrees of greatness were thrust.

That's why Harry Truman (1945-53) usually comes out well. No one expected much of FDR's deputy, but he rose to the challenges he inherited. Yes, I know he dropped the atom bomb of Hiroshima and Nagasaki in 1945. Did it save many Japanese as well as American lives? I have always felt so, but others disagree.

What about the bad guys? The Times puts James Buchanan (1857-61), the Democrat who dithered and drifted towards the bloody civil war that nearly destroyed the union, as No 42, a verdict echoed by other even weightier surveys. Franklin Pierce, his predecessor (1853-57), a drunk and incompetent, was placed second worst.

Myself, I think Rutherford Hayes (1877-81), a Republican elected after a "hanging chads" kind of scandal in Florida, has a lot to answer for. As part of the deal which let him win the disputed election he pulled federal troops out of the occupied south and allowed racist Jim Crow laws to be re-established for the next 80 years.

So does Warren Harding (1921-23) who presided over a post-war boom, marred by red-baiting attacks on civil liberties and spectacular corruption.

Ulysses S Grant (1869-77) also tolerated the "robber baron" era and a depression. Being a great war-winning general was not enough, though another such, Dwight Eisenhower (1953-61), comes out better: a decent man who hated war and warned against the emergence of an over-powerful military-industrial complex.

Under a weak president like Dubya it has become one of the greatest threats to American liberties – and by extension to our own. So how is George W Bush likely to fare at the hands of history?

As with Ronald Reagan (No 8 in the Times list) and Bill Clinton (slapped down to No 23) it's all too soon to be clear. Reagan was very likeable, and his supporters claim he "won" the cold war against the USSR, which first crumbled on his watch. How significant was that? We don't yet know.

Clinton, a man of great potential, was a disappointment. Yet he presided over a successful economy, unencumbered by the huge public debt, which both Bushes helped create. The Lewinsky affair was deplorable, but some of his tormentors in Congress were exposed for hypocrisy on a far bigger scale.

George W Bush has particular problems. History's verdict on his Iraq war depends on how the Middle East evolves over the next 20 years and beyond. If more stable and successful states emerge, their citizens healthier, wealthier and happier, then the Bushites may claim some credit.

And vice-versa. As for the post 9/11 "war on terror" it was misconceived and overblown. Domestic civil liberties suffered – most conspicuously at Guantánamo Bay – taking America's "soft power" reputation down around the world. The courts will one day declare the policy to have been unconstitutional.

It's Bush's domestic economic record which may push him close to the bottom of the league – where many Americans already put him, albeit prematurely. He was dominated by highly ideological officials who slashed the wrong taxes for the wrong people (rich ones), allowed a budget surplus to become a huge deficit and spent like drunken sailors.

Worse, an unsustainable boom turned into the past year's dramatic bust. Rightwing free market theorists have been forced to nationalise banks. If that all wasn't enough there was the shameful neglect of Hurricane Katrina: another avoidable bust which destroyed much of the great American city that was New Orleans.

So President Obama or President McCain – my caution persists until the votes are all counted - will inherit a heavy burden, with expectations on the frontrunner recklessly high. George W has been hidden throughout much of the campaign. You could almost feel sorry for him.

But hey's this is America. So let's end as Americans try to do, on an optimistic note. Lincoln was the country's greatest president because he was a leader who combined low political cunning, the ability to master men and events, with heady rhetoric and a moral vision expressed in simple, stirring English, the language of the King James Bible, Shakespeare and the founding fathers. He saved the union – what he called 'the last, best hope of mankind".

If you haven't read Lincoln's Gettysburg Address lately, here it is, delivered in 1863 on the site of a bloody, recent battlefield where the confederacy's last attempt to split the union north of Washington. Just 272 words, mocked (by the London Times!) as inadequate at the time, it's what we'd now call a pretty good Victorian soundbite.

I like to think that Honest Abe, up there on his cloud, will be watching the count tonight, along with the countless million ghosts of the Atlantic slave trade. Who'd have thought it, eh?