Rupert Cornwell: August was the cruellest month for Obama

What has gone so wrong, so fast? For much of the rest of the world Barack Obama still shimmers in glory. Not so, however, at home – the one place it really matters.

Yes, it really was only eight months ago that he entered the White House with a tail wind of goodwill that no incoming American president in a couple of generations had enjoyed. Today the reverse is true. No new president in half a century has descended to earth with such a bump. July was a bad enough month but August was positively brutal. Unruly town-hall meetings across the country revealed the depths of public suspicion about his signature issue, health-care reform.

Ted Kennedy died, depriving Obama of the legislator who symbolised the reform effort. Personally, he is still well-liked, though not as popular as when he came to office. But his job-approval rating, once over 70 per cent, has continued to slide, to 50 per cent or less at the latest count. So what has gone wrong?

In one sense the answer is simple. Like almost every democratically leader, Obama is finding out that governing is far more difficult than winning elections. Change was a seductive mantra during the campaign, when anything was preferable to George W Bush. Now Americans feel they are suffering from a surfeit of change.

Never let a crisis go to waste, said Rahm Emanuel, White House chief of staff and Obama's chief enforcer, explaining why the economic shambles the new administration had inherited would make it easier to act on other fronts as well. That may have been true early on. But, as spring turned into summer, the mood of the country changed. Total economic meltdown, it was clear, had been averted. Change elsewhere, though still theoretically desirable, seemed less urgent: why the rush to reform, at vast extra expense, a health-care system that for the majority of people seemed to work reasonably well?

There are two basic truths about the United States. It is a conservative country and, for better or worse, it is deeply suspicious of government. Obama, with his blizzard of plans for a re-ordering of financial regulation, energy policy, and health care, not to mention the federal rescue of a hardly deserving car industry, seemed to be ignoring both. And so took root a sneaking fear that his opponents in 2008 were right after all. This mould-breaking leader, who five years ago was still a senator in Illinois, simply had too little experience for the job.

Indeed, it's impossible to resist comparing him to the neophyte Bill Clinton and his botched attempt to reform health care. Back then the Clintons tried to impose their plan on Congress, which was not amused by the impertinence. Obama has done the opposite, giving the legislature free rein to draw up a reform bill. The result however has been much the same: infernally complicated proposals to tackle an infernally complicated issue.

The Clintons' scheme of course never made it to the floor of the House and Senate. Obama probably will secure some bill. But by choosing a middle way, on health care and other issues, he has disappointed both liberal and conservative wings of his Democratic party. If you please no one you must be doing something right, it is tempting to say. But in politics, pleasing no one can be fatal.

Making matters worse is Congress itself, more rancorous and partisan than ever. If anything, the lawmaking process is even more dysfunctional than the health-care system it is attempting to change. Congress happens to be run by Obama's own party, and not a few Democrats are bracing themselves for a mid-term election defeat in 2010 reminiscent of the wipe-out under Clinton in 1994.

But another, even darker, fear intrudes. Maybe the job of American president is these days too much for any individual. In truth we were crazy to think that Obama somehow would make everything come magically right. He has inherited – from his predecessor but also from history – a near unplayable hand.

Health care is only the most visible part of his difficulties. Congress may well fail to pass a green energy bill that is the bare minimum for a credible US contribution to December's climate change conference in Copenhagen. The financial crisis seemingly over, Wall Street appears to be winning its fight to prevent new legislation that would seriously cramp its style.

Then there's Iraq, as well as another unpopular conflict in Asia in which Washington, having aligned itself with a corrupt government embroiled in a long civil war, now must decide whether to raise the stakes further by sending more troops. Afghanistan, once the "good war", isn't Vietnam yet – but who knows?

More broadly, Obama must manage the long-term relative decline in US power that is underway. America, as its politicians love to remind us, may be the mightiest military power. It also happens to be the greatest debtor nation in history – and the creditors in Japan, China and elsewhere are starting to get restless. Back on that brave inaugural dawn of 20 January, all these inconvenient facts were forgotten amid euphoria that the Bush incubus had been lifted at last. But no longer.

After his wretched summer, Obama begins his counteroffensive on Wednesday with a prime-time address to Congress, setting out his own health-care vision in detail. Hitherto, oratory has been his salvation – at the Democratic convention in 2004 when he burst upon the national stage, with his speeches on race during the campaign, and to the Islamic world in Cairo earlier this year. But this time there is no guarantee of success. The risk if anything is of over-exposure – that after eight hyperactive months, his countrymen will be tempted to tune Obama out, just as they tuned Bush out before him. And the last thing anyone needs is another failed American presidency.