As a candidate, Barack Obama pledged "we will kill bin Laden" by striking in Pakistan, if necessary, without that country's consent.
He drew intense criticism from all corners, even from Joe Biden, the Delaware senator who became his vice president, and Hillary Rodham Clinton, his chief rival for the Democratic nomination who is serving as his secretary of state. But Obama didn't waver. And as president, he delivered.
Now, in the early days of his re-election campaign, Obama is in a clear position of political strength as Americans finally are able to savor the death of the man responsible for the Sept. 11 attacks. Republicans who have long and successfully painted Democrats as weak on national security face a far tougher task in making that case against a triumphant Democratic incumbent.
"The world is safer. It is a better place because of the death of Osama bin Laden," Obama said Monday in a statement certain to become a staple of his speeches in the presidential race.
Yet, the war in Afghanistan still rages, and troops continue to die on Obama's watch. He's under pressure to find an exit strategy from a conflict that he dramatically grew by boosting the number of U.S. forces. And the threat to U.S. security didn't disappear with the killing bin Laden.
"Bin Laden is dead. Al-Qaida is not," CIA Director Leon Panetta reminded agency employees.
In political terms, Obama is certain to reap political benefits from the killing of bin Laden after a decade-long, frustrating manhunt. The success inoculates Obama from GOP-led criticism that he's not tough enough to take on terrorists, not experienced enough to be commander in chief, and not decisive enough to lead a country still vulnerable to attacks.
It's questionable whether the bump in support will be permanent.
Americans, after all, are still worrying about an unemployment rate that's hovering around 9 percent. They're stressing over $4 a gallon gas prices that are straining family budgets. And they're still fretting about the long-term fiscal health of the country in an era of soaring national debt and trillion-dollar federal deficits.
Still, Obama _ the candidate of change four years ago _ has an enormous victory in his pocket as he seeks to persuade voters to stick with the status quo.
John Brennan, an assistant to the president for homeland security and counterterrorism, called Obama's decision to go after bin Laden "one of the most gutsiest calls of any president in recent memory."
Even former Vice President Dick Cheney, the Republican who emerged as Obama's chief critic on national security matters, offered praise. "President Obama and his national security team acted on the intelligence when it came in and they deserve a lot of credit, too," Cheney said.
Senate Armed Services Committee Chairman Carl Levin, D-Mich., said the president deserves a boost in polls. "He carefully took information, weighed options" instead of bombing the compound months ago, Levin said. "He followed a more thoughtful course, a more careful course with huge risks. He sometimes is accused of being too thoughtful. In this case, his thoughtfulness, his caution really paid off."
To his detractors, Obama now can say: I told you so.
It was Aug. 1, 2007, when the freshman senator from Illinois pledged to redirect resources to Afghanistan, the war that was overshadowed by the Iraq conflict, and warned Pakistan, where bin Laden was suspected of hiding, that he would use military force if necessary to root out terrorists.
"If we have actionable intelligence about high-value terrorist targets and (Pakistan) President (Pervez) Musharraf will not act, we will," Obama said then.
He was forced to defend his position again a year later during debates with Republican presidential nominee John McCain.
"If the United States has al-Qaida, bin Laden, top-level lieutenants in our sights, and Pakistan is unable or unwilling to act, then we should take them out," Obama insisted. He also made the pledge: "We will kill bin Laden. We will crush al-Qaida. ... That has to be our biggest national security priority."
More than two years after he took office, he made good on that vow.
Armed with intelligence showing bin Laden living in a secure compound outside of Islamabad, Obama authorized U.S. military action without Pakistan's consent and bin Laden died in the ensuing firefight.
It was a defining moment in his presidency, and one that has already started reshaping the 2012 presidential race, removing a key argument from Republican opponents.
The GOP, which long has had the advantage in polling on national security and foreign policy issues, now has a less-potent political weapon to use against Obama after years of painting Democrats, John Kerry and Al Gore among them, as soft on national security issues.
Obama's announcement late Sunday night immediately overshadowed the muddled race for the GOP presidential nomination on what was supposed to be a big week. The party's first debate is set for Thursday in South Carolina and several potential candidates _ Indiana Gov. Mitch Daniels, former House Speaker Newt Gingrich and former Utah Gov. Jon Huntsman _ were said to be nearing decisions on whether to run.
Bin Laden's demise also made all the latest headlines out of that race _ potential candidate Donald Trump's questioning of Obama's birthplace _ seem small by comparison.
The GOP candidates were left with little to say beyond praising the U.S. military and warning against complacency in the fight against terrorism.