Then there was this: President Obama’s second inaugural address, given Monday, was heavy on liberal domestic issues, light on signs that he intended to exercise strong leadership abroad in his second term. “There is an assumption that you can push the pause button” on foreign affairs while internal debates dominate, complained Vali Nasr, dean of Johns Hopkins University School of Advanced International Studies and a former top Obama administration official.

Put those two together, and WEF attendees were asking: Was Obama, whose military intervention policy was once described by an adviser as “leading from behind,” consciously ceding the American position as economic world leader? And if so, was any other country remotely equipped to fill the void?

On Thursday morning, the answer came in from London: British Prime Minister David Cameron stepped up to the podium to audition for that role. In his Thursday morning address, Cameron — fresh from handling a terrorist attack in Algeria that left at least 37 dead — declared that we are in a “long struggle against murderous terrorists.”

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But it was on the economic front that Cameron especially showed muscle to charge ahead. European leaders, and some UK business chiefs, were still reeling from the Prime Minister’s Wednesday announcement that he planned to renegotiate his country’s terms of membership in the EU — seeking to reduce regulation on business, for example — and then let British voters decide if they still wanted to be part of the union.

On Thursday, though, Cameron spoke out in a different role — as president of this year’s G-8. In that capacity, Cameron announced an “aggressive, pan-continental drive to unleash enterprise.” Already, he noted, the UK has cut the corporate tax rates and reduced regulation, and sent huge trade delegations to growing economies with the message that “Britain is back open for business.”

Now, he said, he plans to tackle corporate tax evasion and avoidance, to make the system fairer and more competitive. “When one company doesn’t pay the taxes they owe, then other companies end up paying more. When some cowboys play the system all businesses suffer the fall-out to their reputation,” he said.

Contrast that to Washington, where both Republican and Democratic lawmakers (and the White House) have given only lip service to corporate tax reform — which holds out the promise of boosting GDP and bringing offshore capital back home for U.S. investment.

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Obama is fond of attacking corporations for tax avoidance; it plays well on the campaign trail. Cameron is on a mission to light the rocket engines under economic growth: He dramatically reduced his country’s corporate tax rate — and only now is going after the loopholes.

Cameron wants to give small businesses, “engines of job creation,” an exemption from burdensome EU regulations. In the U.S., small businesses cite regulatory burdens — including the costs of Obamacare — at the top of the list of factors holding back their growth.

Cameron plans to lead the charge on “actively, aggressively” pushing for free trade agreements, including one between the European Union and the U.S. that he said would mean millions of jobs – on his side of the pond alone. Under Obama, free trade deals have ground to a halt, even as other countries continue to churn out bilateral agreements with each other.

Obama may be home-focused, but events have a way of interrupting that intention — following the inauguration this week, legislators hosted Secretary of State Hillary Clinton for a grilling on the attacks in Benghazi and Sen. John Kerry for a round of questions about potentially taking over Clinton’s job. But Cameron sees a vigorous free global market as a force for good.

Cameron has been to the WEF seven times; three as Prime Minister. For the populist-minded Obama, the optics of attending Davos don’t fit: this is a viper’s den of financial elites, the 1% of the 1%, brimming with “millionaires and billionaires” who — he likes to remind voters — don’t carry their “fair share” of the nation’s financial burden.

But Cameron was more than pleased to step up to the plate as a clear champion of the free market, even as he makes bold plans to level the playing field. “I yield to no one in my enthusiasm for capitalism,” he said. “I will have no truck with those who want to demonize the successful.” Which begs the question: Did Cameron have his U.S. counterpart in mind with that not-so-subtle dig?