Iraq, Afghanistan, North Korea, Libya, Iran, Syria, Ukraine... Five years into his presidency, Barack Obama has had plenty of opportunities to confront foreign policy challenges.
Given the wealth of data points, analysts have started attempting to glean what, if any, principles undergird Mr Obama's foreign policy.
The BBC's David Botti surveys Mr Obama's foreign policy record, and public reaction to it, during periods of global unrest in this week's edition of Face Facts.
"Urge restraint," Botti says. "It's become a phrase used often by the administration."
Fred Kaplan writes in Politico that Mr Obama subscribes to a "realist" view of foreign policy, where he coldly acts in the nation's interest and is not animated by idealism - a modern-day Richard Nixon, in effect.
Kaplan writes: "He seems unmoved by the triumphalism that animated George W Bush's foreign policy, in part because he sees the bloody, futile legacy it left in the sands of Iraq - but also because it's just not his style."
New York Magazine's Jonathan Chait doesn't quite buy this line, however, arguing that the Obama foreign policy is a practical form of idealism. He may harbour lofty principles, but he understands that there are not always good solutions, as in Syria.
Mr Obama's idealistic nature revealed itself with the intervention in Libya, Chait contends, where there was no direct US interests at stake.
"The United States had no 'interest' in preventing Muammar Gaddafi from slaughtering civilians, let alone in toppling his regime," he writes. "Indeed, the geopolitical ramifications cut in the reverse direction."
"Obviously, Obama is no George W Bush. On the other hand, nobody else is George W Bush, either. Most American presidents fall somewhere on the continuum between Bushian crusading moralism and Nixonian ruthlessness. Obama does, too.
"With the Ukrainian situation still unfolding and more potential challenges looming on the horizon, there's plenty of opportunity for Kaplan, Chait and countless others to be proven right - or wrong."
Regional arms race and the businesses that profit from it - China's move to increase defence spending by 12.2% will make waves in the surrounding region, much to the benefit of Western military contractors, writes Bloomberg View's William Pesek.
The international community is looking on as Asia engages in a dangerous arms race, which has already come close to being deadly. And the increased spending won't help.
Diplomatic hypocrisy between Russia and the West - Vladimir Golstein of al-Jazeera points a finger at the West for chastising Russia's treatment of Ukraine, while treating Russia the same way.
Since the collapse of the Soviet Union, the West has continued to treat Russia with contempt, and the de facto opinion is that the country itself is malicious.
If that way of doing business doesn't change, he writes, "the next Russian political leader might be less accommodating than Putin, whose foreign policy was to give the West everything it wanted while getting very little in return".
Britain in bed with Russian money - If you want to understand the UK's response to the Ukrainian unrest, writes the Daily Beast's Michael Weiss, you just need to follow the paper trail that serves as a diplomatic shield for Vladimir Putin.
All he has to do is wait for Ukraine's economy to collapse and save the day, knowing that no European country is going to intervene and risk losing Russia's valuable investments.
Anti-gay could be anti-health - Because the new anti-gay legislation passed in Uganda criminalises the act of counselling or aiding another person to engage in homosexual acts, in an article posted on the Week, Vanessa Kerry, CEO and founder of Seed Global Health, worries that the country's healthcare system could suffer.
Doctors will have to take into account the risks of disclosing the sexual orientation of their patients and will pause before sending aid to Ugandans who are at risk if other people know their orientation.
US response is self-centred - Steve Chapman writes for Reason that Americans have not come to terms about how little the US matters in Ukraine.
Beyond that, instead of focusing on how to help Ukrainian citizens, we are using the conflict to launch a political smear campaign.
'So last year' can be a good thing - Bloggers are all but in lockstep, agreeing that the once-hip Berlin is just not as cool as it used to be. And while you would expect residents to mourn the loss of their city's status, Feargus O'Sullivan writes for the Atlantic that they couldn't be happier.
Because of a West v East divide that has persisted since the destruction of Berlin Wall, increasing rent prices and a shifting social scene, most Berliners are looking forward to the exodus of these trendy foreigners.
The bottomless hole - Leo McKinstry is fed up with having to pay for the EU's mistakes. Writing for the Daily Express, he says that the organisation's arrogant overspending, especially the recent revelation that the EU went over its budget by £20bn ($33.5bn), borders on disdain for the everyday citizens who he says shell out cash to plug holes in the EU's sinking ship.
"Self-satisfied pro-Europeans love to sneer at the follies of US capitalism yet in its addiction to creative accounting the EU far exceeds anything achieved by oil company Enron," he contends.
Lots of green thumbs, but no way to use them - "Poor communication between the agriculture, environment and agroforestry sectors will keep Africa waiting for a 'green revolution' a little longer," writes Isiah Esipisu for Daily Nation.
Although there is great potential for the continent to increase food production, progress is stymied over and over by a lack of co-ordination. Agriculture leaders need to sit down and commit to an integrated system to move Africa's agricultural production into the future, he writes.
BBC Monitoring's quote of the day
Arab perspective on the crisis in Ukraine: "The US says that Russian intervention is in breach of international law. However, international law does not apply to the powerful. Whoever gave the US the right to occupy Iraq with no justification will surely not deny Russia the right to intervene to protect its interests." - Fahad al-Fanik in Jordan's Al-Ra'y
One more thing…
The joke's on you, David Cameron - the Prime Minister's earnest tweet about his work with President Obama on a solution to the situation in Ukraine became the butt of a joke that brought together a Massachusetts-based comedian and an award-winning English actor, as well as the rest of the internet.
Patrick Stewart and Rob Delaney fired the first shots, responding to the serious-faced photo of Mr Cameron on the phone with Obama by recreating the scene with a tube of toothpaste and a container of wet wipes.
"I'm now patched in as well. Sorry for the delay", tweeted Mr Stewart. After a flurry of other Twitter users jumped into the fray, using their own household objects, David Cameron finally responded with a picture of him talking to Bill Clinton.
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