Barack Obama promised a sharp break from the Bush era, yet he seems to have stepped into the shoes of his disgraced predecessor. As the anniversary of his election approaches, Mehdi Hasan investigates what went wrong

On health, he has proposed reforming the system of care that leaves 46 million Americans uninsured, but has retreated at the first sign of trouble, backing down on the "public option" - a government-run rival insurance plan - even though it may be the only method of ensuring that the private insurance industry so beloved of the Republican Party is exposed to real competition and challenge.

On climate change, Obama, unlike Bush, has recognised the need to combat global warming. Like Bush, however, he has failed to persuade Congress to take substantive action on emissions and has yet to pledge significant financial support for developing countries to help them cope with the coming climate crisis. His rhetoric may have shifted since the late 1990s when, as a state senator, he lent his support to a bill condemning the Kyoto Treaty, but it has yet to be matched by action.

One of Obama's executive orders calls for an increase in motor vehicle mileage standards, but this will only, in the words of Steven Hill of the New America Foundation, "push fuel efficiency by 2020 to a level that European and Japanese cars reached several years ago, and which even China has already achieved". Meanwhile, in May, the administration opted to retain, despite Congressional support to overturn it, a Bush-era rule that limits protection for polar bears in the Arctic - classed as an "endangered species" by the US Environmental Protection Agency - from the effects of global warming.

On financial reform, Obama has been accused of being a "socialist" and a "Marxist", intent on nationalising the US economy. The fiscal reality is, however, very different. The multibillion-dollar bank bailout, approved by Bush, has simply been continued by Obama in the same vein (his treasury secretary, Tim Geithner, worked closely with the Bush administration as president of the New York Federal Reserve). Obama has tried to rein in bank bonuses and failed. Goldman Sachs and JPMorgan - recipients of bailout aid - paid out billions more in bonuses in 2009 than in 2008. Meanwhile, he has continued to defend executive pay on Wall Street and set himself against European proposals to regulate remuneration or impose a cap on bonuses.

Obama came to power with a "firm pledge" not to raise "any form" of taxes on families making less than $250,000 a year. However, despite an off-the-cuff remark that he wanted to "spread the wealth around", his tax plans have done little to advance even modest social-democratic goals. As the treasury department's "Green Book" on revenue proposals has acknowledged, "The [Obama] administration's primary policy proposals . . . [make] permanent a number of the [Bush] tax cuts enacted in 2001 and 2003."

Diane Lim Rogers, chief economist at the bipartisan fiscal think tank Concord Coalition, told me that "almost all of the tax policy proposed in the Obama budget is just a continuation of the Bush tax policy". Under the "Bush-Obama tax cuts", the only income group not to benefit is the top 0.1 per cent - households with an annual income of more than $2.7m. Like Bush, Obama seems keen not to upset or disturb the rich and powerful.

On torture and Guantanamo Bay, Obama was praised for announcing, in his first week in office, that the world's most notorious prison camp would be closed within a year and that torture - including the Bush-approved technique of "waterboarding" - would be outlawed. Last month, however, with Congress refusing to agree to closure, the Pentagon's top lawyer, Jeh Johnson, said the administration was committed to shutting Guantanamo Bay by early 2010, but stopped short of confirming it will happen. According to the Columbia University law professor Scott Horton, force-feeding operations have continued at the camp, and are apparently administered with "such violence and brutality" that one prisoner has died.

Meanwhile, in Afghanistan, the US is increasing its capacity to imprison people by expanding facilities at bases such as Bagram, where human rights groups have documented many incidents of torture and several unexplained deaths in custody. In February the new administration told a federal judge that military detainees there have no legal right to challenge their captivity. So much for ending the Bush administration's policy of indefinitely detaining "enemy combatants" without trial.

Obama has refused to release the shocking photographs of the Bush administration's "enhanced interrogation" techniques, as well as CIA documents describing those interrogations. He has criticised Senator Patrick Leahy's proposal for a "truth commission" to investigate the Bush administration's national security policies, and backed immunity for senior Bush officials implicated in torture. In effect, he is covering up the torture he decried as a presidential candidate. As the neoconservative Charles Krauthammer wrote with glee in May: "Observers of all political stripes are stunned by how much of the Bush national security agenda is being adopted by this new Democratic government."

It is on foreign policy, and the "war on terror" in particular, that Obama was expected to make the biggest break with the Bush regime. Early on, he announced that he would begin winding down the war in Iraq - but only, it seems, in order to divert US troops, spies and diplomats to the war in Afghanistan and operations across the border in Pakistan. He has approved air strikes there that have killed more civilians in nine months than died in US bombings in the final year of the previous administration.

It may have been Bush who invaded Afghanistan eight years ago, but that conflict should now be seen as Obama's war. With the support of a key holdover from the Bush administration, the defence secretary, Robert Gates, Obama has sent more than 30,000 extra troops to Afghanistan since May - almost doubling the US contingent.

The pressure for more troops is being kept up by Obama's new commander on the ground, Stanley McChrystal. In true Bush style, Obama suddenly replaced David McKiernan with McChrystal in May. McChrystal is an odd choice for a liberal president and critic of the Iraq war: a favourite of Dick Cheney and Donald Rumsfeld, he has been accused of overseeing torture and human rights abuses, under Bush's presidency, at Camp Nama in Iraq, during his deployment there as a special forces commander.

If he is to chart a course independent of the war crimes, torture, chaos and general lawlessness of the Bush years, Obama has to start with the Afghan debacle. He can, in the words of the New York Times columnist Frank Rich, emulate President John F Kennedy's decision-making on Vietnam, and resist lobbying by military leaders and a hawkish media for more troops and more war, or he can continue down the Bush road of perpetual war for perpetual peace.

Obama will have to act soon to reverse the slide in his ratings, to reassert his authority at home and abroad, to keep his army of liberal Obamaniacs on board. Disenchantment and disillusionment with the candidate of change are beginning to harden. Some will argue that the left is forever prepared to scream "betrayal" at those it elects to power - be that Lyndon B Johnson, Harold Wilson, Bill Clinton or Tony Blair. But the case of Obama is different.

With his presidential campaign, the former Illinois senator raised the hopes of millions of people across the US and the world to an extent never seen in modern politics, talking repeatedly of change, reform and renewal, and suggesting he would erase the legacy of his disliked and disgraced preomgdecessor from day one. It was inevitable that even the slightest sense of continuity in policy, personnel or practice would disappoint, as it has. Obama, however, has gone further, adopting his predecessor's positions on a wide variety of issues, from the parochially domestic to the grandly geopolitical.

The lawyer Jon Eisenberg, who continues to battle the Bush-like Obama justice department in the courts, has been a registered Democrat for 30 years. He considers himself to be a "moderate leftist" and echoes the opinions of growing numbers of Americans: "I voted for Obama - even contributed a substantial amount of money to his campaign. I want my money back."