In February 2008 I met American friends in New York at a diner in downtown Manhattan. It was two days after Super Tuesday and the couple had just flown in from Los Angeles, where they live.
My Californian friends were buzzing with excitement at the prospect of the young senator making it to the White House to redeem America's reputation, which had been badly damaged by the incumbent president.
They were sick of George W Bush and his illegal war in Iraq and the devastation it caused. They were fed up of Bush's administration of hawks and hidden agendas with the likes of Dick Cheney, Karl Rove, Donald Rumsfeld, Paul Wolfowitz and Richard Perle wielding destructive power behind closed doors.
They wanted an end to the Bush era of isolationism and unilateralism and they saw Obama representing a new dawn for America.
When Obama won the election that November, my Californian friends were ecstatic. They felt the chapter of havoc wreaked during the Bush era was finally over and they clinked their glasses to celebrate a fresh start.
The response to Obama's victory was similarly upbeat in Ireland and in other countries across the globe. We welcomed his offers of bridge building with the Muslim world. We loved his elegant demeanour and awesome oratorical skills.
The pictures of himself and Michelle and the two girls walking down the corridors of the White House gave us all a lift. We breathed a sigh of a relief that sanity had returned to Pennsylvania Avenue.
Four years on that euphoria has evaporated and many Americans are bitterly disappointed that President Obama has failed to deliver on the promises he made during his election campaign.
My Californian friends regard Obama as an ineffectual leader who has presided over an economic malaise that continues to afflict. They blame him for pandering to Wall Street and for failing to take on the bankers who behaved with abandon.
They berate him for not fulfiling his promise to close Guantanamo Bay prison and for continuing with the draconian security laws brought in during the Bush administration after 9/11.
As a couple with a young child, they pay a sizable monthly sum in health insurance and they had high hopes that Obama's health care reforms would ease that monthly financial burden. Today they say his promised health care for all is nothing more than a sop to enrich private health insurance and pharmaceutical companies and that it will still leave millions unable to access any kind of health care.
They now say that Hillary Clinton would have made a better president and they're sorry they didn't back her. That dovetails with a spate of commentary from the US recently extolling Hillary's record as Secretary of State. There is mounting speculation that she may run for the White House in 2016, despite her insistence today that she has no intention of doing so.
Obama's failure to wrest the US economy out of the doldrums would normally be enough to see him doomed in November. But Mitt Romney's staggering series of gaffes has probably ruined his chances of victory and the scary economic policies of his running-mate Paul Ryan will see many voters running towards the incumbent contender.
Back in 2008, when Obama and John McCain were out on the hustings, one Irish journalist wrote that the American elections were so important we should all get to vote on them. She was dead right.
Despite its ailing economy and the rise of the BRIC countries as emerging superpowers, the US still wields enormous influence. What happens to the American economy impacts on all of us as we so painfully experienced when the Wall Street Investment bank Lehman Brothers collapsed in 2008.
The same can be said for America's foreign policies. Just look at the destruction caused by George W Bush's war in Iraq. Unfortunately Obama's record isn't much better.
While he certainly deserves credit for pulling US troops out of Iraq and for getting rid of Osama bin Laden, he has continued with a failing war in Afghanistan where 2,000 American troops have now been killed and countless innocent Afghans have lost their lives.
Obama's use of drones to take out terrorist suspects in the likes of Yemen, Pakistan and Afghanistan has increased. And civil libertarians have berated him for supporting draconian legislation that enables US citizens to be detained indefinitely if suspected of terrorist activities.
The former presidential candidate Ralph Nader last week described Obama's foreign and military policies as being 'more aggressive more illegal worldwide' than those of George W Bush.
Despite his lofty rhetoric and promises of hope and peace, Obama's legacy so far has been disappointing. Our beacon of hope has dimmed and left us feeling somewhat disheartened.