In that speech, Mr. Obama outlined a vision for a new era of economic cooperation in the Middle East, one of steadfast US support for democracy, and of reset priorities.
"I've come here to Cairo to seek a new beginning between the United States and Muslims around the world, one based on mutual interest and mutual respect," he said then.
While Obama ended the war in Iraq on a schedule provided to him by his predecessor, George W. Bush, many of the promises in that speech went unfulfilled. The Guantánamo Bay military prison was never closed. Progress on peace between Palestinians and Israelis was not made. The promised economic development of Afghanistan, beset by a war that Obama now looks set to end in 2014, never took root.
Nevertheless, four years later, he's got his new beginning – not by his own hand, and not the one he would have either imagined or wanted when he made his series of stirring promises in Cairo.
The self-immolation and death of Mohamed Bouazizi in Tunisia in December 2010 led to the sharpest change in the politics of the Middle East since the 1960s. The events of the past year in Egypt, Syria, Tunisia, and Libya have cemented a radical new reality that Obama will have to contend with in his second term.
For all the talk of a US strategic "pivot" to Asia, a dramatically changed Middle East looks set to suck up a huge portion of American diplomatic energy and attention in the coming years. Old, comfortable patterns of dealing with regional dictators like Egypt's Hosni Mubarak and Tunisia's Zine El Abidine Ben Ali have been severely disrupted. Islamists, long feared by the US, have since won power in free elections in Egypt and Tunisia, and are among those fighting the secular regime in Syria.
In Syria, the civil war has claimed more than 40,000 lives, and there are threats to US interests in both the demise of Bashar al-Assad's regime there, if it comes, and in his survival. As this year draws to a close, the US has edged closer to full-fledged support for elements of the uprising against Mr. Assad even as it labeled one of the opposition's most effective fighting groups, the jihadi Jabhat al-Nusra, a foreign terrorist organization.
The denouement there, when it comes, could well have destabilizing ripples for neighboring Lebanon and Iraq. Syria's chemical weapons stockpiles are a reality that can't be ignored, and the prospect of those weapons falling into the hands of jihadi groups has the Obama administration drawing up contingency plans for possible intervention.
Israel, while it's had a long cold war with Assad's Syria and continues to occupy the Golan Heights, nevertheless is frightened by the prospect of yet another Sunni Islamist regime, rather than a secular nationalist one, on its doorstep.
Troubles at home for Israel
The Israeli-Palestinian conflict is also moving into new, dangerous waters. The so-called peace process that began with the Oslo Accords in 1993 has petered out completely. In 2009, Obama called for an end to Israeli settlement construction in the West Bank and early in his presidency leaned hard on Israeli Prime Minister Benjamin Netanyahu for at least a temporary freeze. But expansion has continued unabated, and the Obama administration appears to have lost interest in pressing the issue.
In the West Bank, Palestinian Authority President Mahmoud Abbas has been weakened by his failure to negotiate an end to the encroaching Israeli settlements, and in Gaza the Islamist movement Hamas remains as entrenched as ever.
In November, Israel was a hairbreadth away from an invasion of Gaza that was only avoided at the last minute by a negotiated cease-fire. A key figure in heading off that crisis was Egypt's president, Mohamed Morsi, the Muslim Brotherhood stalwart whom the US turned to as intermediary with Hamas.
The rise to power of the Islamist Muslim Brotherhood in Egypt captures the peril for the US of this new beginning. Mr. Morsi was elected in a free election, but the country's new constitution, which is set to pass a referendum this month, is filled with alarming elements in terms of personal freedoms and minorities' rights.
The state of that country's economy has deteriorated sharply thanks to the political turmoil of the past two years, with clashes in Cairo between supporters of Morsi and his opponents in November being the latest reminder that the authoritarian stability of the Mubarak years has been replaced by something fluid and hard to predict.
Many of the Egyptian liberals and secularists who listened to Obama's Cairo speech so appreciatively now grumble that he's backing the Brothers as they seek to cement their power and influence over the country. In the year ahead, and beyond, Obama will have to weigh criticism of Egyptian suppression of civil liberties on the one hand against a desire for Egyptian cooperation in keeping Hamas, an offshoot of the Muslim Brotherhood, contained in Gaza.
There are still other shoes to drop in the region. Libya is struggling to create a new order after decades of one-man rule by Muammar Qaddafi, with weapons smuggling rife along its desert borders and sharp clashes there still to be worked out over the role of Islam in the country's political life. In Bahrain, a close US ally and home to the US Navy's Fifth Fleet, a Sunni monarchy is contending with the simmering political discontent of the country's Shiite majority, which is challenging Obama's earlier assertion of a personal commitment to advocating "governments that reflect the will of the people."
East of the Middle East
The one constant from four years ago is hardly reassuring: the slow, steady progress of Iran's nuclear program. Obama has spearheaded an effort among Western governments to financially isolate Iran, with restrictions on its oil sales and the financial transactions of its central bank, which have taken a heavy toll on Iran's economy but have done little to lessen the commitment of Ayatollah Khamenei, the country's supreme leader, to what he insists is a peaceful nuclear program.
For now, Iran continues to insist on its right to nuclear enrichment, which the US argues is producing material that could be eventually used in a nuclear bomb.
The situation in Afghanistan and Pakistan is as fraught as ever. Yes, Osama bin Laden was killed in a daring raid in Pakistan by US troops in 2011. But, notwithstanding billions of dollars in annual US aid, that country continues to provide a home to militants, and Shakil Afridi, a Pakistani doctor who helped the US track Mr. bin Laden to his compound in Abbottabad, remains in a Pakistani jail.
In Afghanistan, the Army is completely reliant on US financing and technical support to operate, and the Taliban appear no weaker than they did when Obama took office.
As the Obama administration looks ahead to 2013 and its new challenges, it is looking over a Middle East landscape transformed from four years ago. The old ways of doing business in the region aren't going to work anymore. How Obama must miss them.