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World leaders welcome Obama's 2nd term - but many challenges wait on his doorstep

Difficult situations remain for President Obama in Syria, Afghanistan, Iran and Israel. NBC's Richard Engel discusses what Obama needs to do to overcome these challenges in his second term.

Updated at 8:32 a.m. ET: LONDON -- World leaders from Mexico City to Beijing were quick to congratulate Barack Obama on his victory early Wednesday – but the re-elected president faces a slew of foreign policy challenges in his second term.

"I would like to congratulate re-elected President Barack Obama from the bottom of my heart," German Chancellor Angela Merkel told local television. "We know each other well and I am looking forward to our cooperation ... My heartfelt congratulations on this day today."

British Prime Minister David Cameron and Enrique Peña Nieto, president-elect of Mexico, both posted goodwill messages on Twitter.

"It will give me great pleasure to congratulate him personally on my next visit to the United States and work together for the benefit of our countries," Pena Nieto said.

PhotoBlog: From Obama's old school to his ancestral village - world reacts to US election

Bars and U.S. embassies threw election-night parties to watch the returns came in. At the Redhook American-themed restaurant in London, many stayed up until 4:30 a.m. local time (11:30 p.m. ET) to watch TV networks call the result for Obama.

"I think he's shown a sort of diplomacy and maturity that maybe under George W. Bush we didn't see," Chris Padden, a 27-year-old education worker, told NBC News. "I think we are hoping that he's going to show the same diplomacy over the next four years."

Kevin Lamarque / Reuters

Campaigning with Mitt Romney and Barack Obama, voting and election results.

Ciaran McCafferty, 30, who works in finance, said: "It's still very exciting, even though it's not our election. The United States is a big player in the world and it's important for everyone's life."

Across the U.K. capital at the U.S. Embassy, one Mitt Romney supporter told NBC's Jim Maceda: "I'm incredibly sad. This has been very long and grueling ... We did every single thing we could."

At an election night party in Frankfurt, Germany, student Teresa Isigkeit said: "I am pretty positive that Obama is going to have a great second term and he is a great president, so that's all we were hoping for."

Dr. Martin Thunert, political analyst at the University of Heidelberg in Germany, added: "I think most people in Germany and many western European countries were hoping for the re-election of President Obama. What I think is important for many Europeans that banking regulations that Obama introduced a couple of years ago will continue. And some were afraid that a Romney administration would repeal that, so I think in that sense they are quite happy."

Watch the drama of election night quickly unfold in a three-minute montage of sights and sounds.

China's Foreign Ministry said President Hu Jintao and Premier Wen Jiaobao phoned Obama to congratulate him. Vice President Xi Jinping, who is to begin taking over this week in China's once-a-decade leadership transition, phoned Vice President Joe Biden to congratulate him.

At a party at the U.S. Embassy in Beijing, student Liu Xin, who is aged in her 30s, said watching the U.S. election was "like a window to learn U.S. politics."

"Personally, I'm in support of President Obama, because I feel himself is a symbol of realization of American dream," she told NBC News.

Special report: NBCNews.com's The World is Watching series

Zindzi Mandela, daughter of former South African President Nelson Mandela, told a party in Pretoria: "As a mother and as a grandmother who raises boy children, I think that the symbolism of having a black man occupy the highest office is something that can make my children very aspirational to know that this is possible, you know, in their lifetime."

In Cairo, retail manager Mohamed Hindawi, 42, stayed up half the night watching the results come in. "Really we are happy, it’s a very good morning," he said. "It’s a very good morning for all the Egyptians, not me, all the Egyptians.  If I were in the states I would vote for Obama.  All of my friends there they vote for him."

In Kogelo village in western Kenya, Obama's step-grandmother Sarah Obama congratulated her grandson on his victory. "Take the great job that people have given to you and lead them well. They have shown immense love to have voted for you," she said.

Ben Curtis / AP

Kenyan villagers ride motorcycles and wave branches to celebrate Obama's re-election in the village of Kogelo, which is home to Barack Obama's step-grandmother on Wednesday.

However, NBC News' Chief Foreign Correspondent Richard Engel said Obama should "enjoy his victory" now,  adding:"Starting very soon, the rest of the world will be crashing down on the president’s doorstep.”

“You have the issue of Syria – a county that is imploding, and a conflict that could quickly spread to other countries in the region. You have the issue of Afghanistan, the war that is still ongoing. The expectation now is there will have to be a refocusing on Afghanistan to try and end that conflict.

“There are many Israelis who are not keen on Barack Obama – they did not want to see him elected,” Engel added.

Israel's Prime Minister Benjamin Netanyahu, who has had a strained relationship with the American president over his policies on Iran and the Israeli-Palestinian conflict, congratulated the president in a text message to reporters. "I will continue to work with President Obama to preserve the strategic interests of Israel's citizens," he said. 

Top 10 foreign policy issues facing Obama

Would a Romney victory have made a difference to the situation in Afghanistan? Not much, according to Daoud Sultanzoy, political analyst in Kabul. "The bottom line would have been the same, I think - just their style of management would have been different.

"Mr. Obama...said some things that were good but he didn’t do them, he didn’t fulfill his commitments when it came to transparencies, when it came to credibility of both side’s commitment and accountability.  He just paid lip service in the past four years and that has damaged the Afghan people."

NBC's Tom Brokaw discusses the unlikely story of President Barack Obama's path to the White House and a second term as president.

In Iran, with whom relations are tense because of Tehran's nuclear program, the semiofficial Fars news agency rolled out the vivid headline, "Republican's elephant crushed by Democrat's donkey." 

Professor Cyrus Izadi, from the department of social science at Tehran University, told NBC News: "There are two camps in Iran. One camp favored Romney because historically the Republicans have been less successful in putting Iran under pressure and they are unlikely to start a war so they would have been better for Iran. Another camp feels that the Republicans are serious about starting a conflict with Iran and it would be better to have Obama leading America because he does not have an appetite for war."

Engel speculated that Obama may seek to use his second term to attempt an Arab-Israeli peace deal to secure his legacy, even though he has already been awarded the Nobel Prize for peace. 

However, NBC Chief Foreign Affairs Correspondent Andrea Mitchell said: "I don't think he's got the opportunity. It has really died on the vine - you don't have the leadership on either side committed on this. I would be really surprise if they could find a way. It is clear this president is going to have to visit Israel, which he didn't do in his first term... and repair damage with Jewish Americans."

The election result made some late editions of European newspapers. "OBAMA WINS" ran the giant front-page headline in the U.K.'s Daily Telegraph.

NBC News' Andy Eckardt, Ali Arouzi, Ed Flanagan, Michelle Kosinski, Charlene Gubash, Atia Abawi, F. Brinley Bruton, Shanshan Dong, Michele Neubert, Peter Jeary and Alastair Jamieson contributed to this report.

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