It is a popular misconception that the US under Barack Obama is a country in decline. But much of the current commentary about it rests on rather loose analysis, on impressions that it has lost its way and that it lacks the will to address the problems it faces.

Given the ill-judged wars waged by President George W. Bush in Afghanistan and Iraq, the poor economic legacy bequeathed to President Obama since 2008 and the large fiscal deficits, combined with the growth of the Chinese, Indian, Brazilian and other economies, a significant and irreversible shift in global economic power seems to have occurred.

But has it? And, with just two years before President Obama vacates the White House, what will be his legacy? Does the belittling of Obama from mainstream commentators about “a rudderless, stalled administration”, even a “failed” presidency, hold water?

There is no argument that Obama’s poll approval rating is low compared with earlier presidents. But polls are not the measure of a president. High office should not be about putting points on the electoral scoreboard. It should be about changing the country for the better.

With two years to go, an objective assessment of Obama’s presidency would notch up more achievements to his name than those of many of his recent predecessors, despite the scorched-earth strategy adopted by the Republican opposition. I believe that President Obama has made the US a better place and that many of his achievements are likely to endure.

When Obama signed into law the Affordable Care Act (“Obamacare”), he took a giant step forward for millions of Americans who until then had had no access to health insurance. Free healthcare, a privilege we in Europe take for granted, had until now been denied to many Americans.

Obamacare has meant a huge improvement to the quality of life of tens of millions of Americans. Not just better medical care, but greater financial security.

Even those who were already insured have gained both security and freedom because they now have a guarantee of insurance cover if they lose or change their job. Health reform will be an enduring legacy that has eluded any of his predecessors. It is a major policy success story.

As to financial reform, although Obama may be criticised for not following the financial crisis in 2008 with a drastic crackdown on Wall Street, the reform bill he signed into law in 2010 (known as Dodd-Frank, a complicated piece of legislation), while it may not prevent another similar financial crisis from happening, will at least make future crises less severe.

Obama may not have introduced the full overhaul of finance many were urging, but what he introduced is better than nothing.

It is disappointing that six years into his presidency, the US economy is still some way from full recovery. But the fact is that matters could have been far worse given the devastation the financial crisis wrought across the world.

Recovery has been slow. It has taken almost six years for the US to regain pre-crisis average income. But when compared with that of the European Union, theUS performance has been substantial. Unemployment in the US rose to 10 per cent in 2009, but it has come down sharply in the past few years.

By comparison, Europe has had barely any job recovery at all and unemployment is still in double digits.

Obama’s policies undoubtedly contributed to this better performance. There is strong consensus that his stimulus plan helped to mitigate the worst of the slump. The bottom line is that his policies helped the economy.

I believe that President Obama has made the US a better place and that many of his achievements are likely to endure

While there was enormous human and economic damage on his watch, the US has managed the financial challenge better than most countries facing comparable crises, not least Europe.

His record on national security has left some early Obama supporters bitterly disappointed. Many hoped that he would hold to account the people who took the US to war in Iraq on false pretences. None of that happened.

As to his conduct of foreign policy, Obama has been reluctant to commit US ground forces and eager to extract them from ongoing military commitments. I personally approve of his reluctance to go to war gratuitously – as his predecessor did – and that is to be welcomed compared with the alternative.

His most recent decision to use special executive powers to grant up to five million undocumented immigrants or their children protection from deportation was brave and honourable.

US immigration policy has been a dysfunctional mess. Fixing it had become a pressing legal and moral emergency. His executive order could be scrapped by a future president, but it is an undoubted step in the right direction.

The overall verdict with two years to go? President Obama has delivered less than his supporters wanted, but more than his detractors acknowledge. His health reform is imperfect, but still a giant step forward.

Financial reform fell short of what should have happened, but is more effective than has been credited. Economic management has been much better than in other advanced countries. National security has been marked by a welcome lack of adventurism.

On any measure of the basic indicators – what the Chinese call “comprehensive national power” – American dominance still reigns supreme.

Starting with the first measure of power, the size and influence of the US economy relative to others, the US share of the world’s GDP has held remarkably steady, and not only over the last six years but over the past 45.

American GDP, at roughly a quarter of the world’s economic output, remains roughly the same as it was in 1969. It remains not only the largest but also the richest economy in the world.

China’s huge rise has come largely at the expense of Europe and Japan. While getting closer in size to the US’s economy, it has yet to eclipse it.

Secondly, what about the magnitude of its military power compared with that of potential adversaries? Here, the US remains unmatched. It is by far the most powerful military nation the world has ever known.

There has been no decline in the US’s relative military capacity, though painful cuts in the defence budget are being made.

The US armed forces are equipped with the most advanced weaponry and are the most experienced in actual combat. They could defeat any other nation in a head-to-head battle.

As to the third measure of national power – the degree of political influence it wields – of course the US is not able to get what it wants all, or even much, of the time.

Although the challenges today are great, and the rise of China is the most obvious, they are not any greater than those America faced during the Cold War.

While China’s task as the rising great power is to push the US out of its present position, the US has only to hold on to what it has.

Although President Obama has not lived up to the rhetoric and golden dreams promised in 2008, it matters that, in the face of the most obstructive Republican opposition ever and the worst financial crisis for 75 years, he has achieved so much of lasting value.