(CNN) -- The next U.S. president will face a world fraught with far more foreign policy challenges than President Bush did when he took office.
The next president will have to decide whether U.S. troops stay in Iraq or begin a withdrawal.
The possibility of the first female or African-American U.S. president, coupled with the desire of many around the world to move beyond eight years of the Bush administration's foreign policy, which has been viewed by many as divisive, has resulted in particular interest in the Democratic race.
With less than a year remaining of the Bush presidency, the new president will take office in January with wars in Iraq and Afghanistan, the global campaign against terrorism and the nuclear ambitions of Iran and North Korea already on the agenda.
Add to that the image of the United States around the world -- now at an all-time low -- and the rise of India and China as world powers, and the next president's plate is already full before the nominees have been officially decided.
To say "the world is watching" the election would be an understatement. In fact, it has attracted an unprecedented level of interest overseas. Arab satellite networks are shelling out big bucks to send reporters to trail the candidates around the country.
Foreign diplomats have traveled to primaries such as Iowa and New Hampshire and confess their governments are far more interested in discussing the latest from the campaign trail than they are talking about the dry diplomatic issues of today.
The expected Republican nominee, Sen. John McCain, has been touting his years of foreign policy experience as a reason to choose him over Sen. Hillary Clinton or Sen. Barack Obama in November. Watch Clinton suffer blow as McCain, Obama clash on Iraq »
He voted for use of military force in Iraq and supported President Bush when he vetoed the war spending bill that would have withdrawn most U.S. troops by March 2008. He was, however, an outspoken critic of Bush's former defense secretary, Donald Rumsfeld.
McCain was an early proponent of sending additional American troops to Iraq, otherwise known as "the surge," which he and other officials have credited for reported dips in violence in Iraq.
McCain has said he expects a smaller but long-term American presence in Iraq similar to those in South Korea or Kuwait.
On the surface, the Democratic candidates aren't that far apart from one another on foreign policy. Although Obama opposed the invasion of Iraq before joining the Senate and Clinton voted for it, both now favor a phased withdrawal of U.S. forces and the need for Iraqi forces to take over security.
Both Clinton and Obama say they would not rule out the use of force, even unilaterally, to protect U.S. national security interests. Both support multilateral engagement and diplomacy with enemies like Iran. In the Middle East, they both support a two-state solution to the Israeli-Palestinian conflict, while maintaining a pro-Israel tone. Both call for a redoubling of efforts in Afghanistan.
But their real differences surface in style and tone. Citing eight years as first lady and two terms as a senator, Clinton has sought to portray herself as the strongest candidate on foreign policy, criticizing Obama for thin credentials.
During a foreign policy speech this week at George Washington University, Clinton waved the specter of the Bush presidency. Watch Clinton, Obama debate foreign policy »
"We've seen the tragic result of having a president who had neither the experience nor the wisdom to manage our foreign policy and safeguard our national security," she said. "We cannot let that happen again."
Clinton has criticized Obama for saying he would attack al Qaeda targets in Pakistan, even without the approval of the Pakistani government. Last summer Obama made headlines when he said, "if we have actionable intelligence about high-value terrorist targets and President Musharraf won't act, we will."
During Tuesday's debate, Obama noted the Bush administration did exactly that recently when it launched an airstrike on a top al Qaeda leader without telling the Pakistanis first.
Obama has sought to turn Clinton's competition on experience into one about judgment, arguing Clinton "lacked the good judgment" to oppose the Iraq war from the beginning.
"Once we had driven the bus into the ditch, there were only so many ways we could get out," he said during Tuesday's debate in Ohio. "The question is, 'Who's making the decision initially to drive the bus into the ditch?' "
One stark difference between the candidates is on talking with so-called dictators. Obama has said he would meet with the leaders of Iran, Syria, Venezuela, Cuba and North Korea in the first year of his presidency, arguing "it's important for the United States not just to talk to its friends, but also to talk to its enemies."
Last summer during a CNN/YouTube debate, Obama called it "a disgrace that we have not spoken to them."
Taking a page from the late President Ronald Reagan, who engaged the Soviet Union even as he called it the "evil empire," Obama said "the notion that somehow not talking to countries is punishment to them -- which has been the guiding diplomatic principle of this administration -- is ridiculous."
While Clinton herself has called for more diplomatic engagement with U.S. foes, she called Obama's approach "irresponsible" and "naive."
"We simply cannot legitimize rogue regimes or weaken American prestige by impulsively agreeing to presidential-level talks that have no preconditions," she said at George Washington University. "It may sound good, but it doesn't meet the real-world test of foreign policy."
The candidates seem to differ most on the issue of Cuba. Both call for a democratic transition, but Obama has called for lifting of the ban on travel and remittances on Cuban-Americans.
Earlier this week Obama called Fidel Castro's resignation "the end of a dark era in Cuba's history" and said the U.S. should prepare to "begin taking steps to normalize relations and to ease the embargo of the last five decades."
Clinton supports the U.S. embargo and says only that she would "engage our partners in Latin America and Europe who have a strong stake in seeing a peaceful transition to democracy in Cuba." She said she wouldn't meet with Cuba's new leader, Raul Castro, until "there was evidence that change was happening." E-mail to a friend
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