It's not only on these core assumptions that the candidates share a broad agreement. These principles translate into specific policies where it would be tough to tell the difference between a Romney and an Obama presidency:
Iran: Sorry, I just don't see any significant difference between the way Obama is handling Iran's nuclear program and the way Romney might as president. And that's because there's seems to be an inexorable arc to the Iranian nuclear problem. If by 2013 sanctions and negotiations don't produce a sustainable deal and Iran continues its quest for a nuclear weapon, one of two things is going to happen: Israel is likely to strike, or we will.
If it's the former, both Obama and Romney would be there to defend the Israelis and manage the mess that would follow. Both would be prepared to intercede on Israel's behalf if and when it came to that. As for a U.S. strike, it's becoming a bipartisan article of faith that the United States will not permit Iran to acquire a nuclear weapon. And both men are prepared to use military strikes against Iran's nuclear sites as a last resort, even if it only means a delay (and that's what it would mean) in Iran's quest for nukes.
Freedom Agenda: The bloom went off this rose in George W. Bush's administration. The Arab Spring has turned into a long cold winter -- the prospects for the quick and easy rise of democracies in the Middle East are slim to none. A Romney administration might produce a tougher tone in defense of freedom (without any meaningful action) and perhaps more negative rhetoric about Islamists, but would also confront the same bad options and limited leverage Obama has now. On Egypt, Syria, Bahrain, Yemen, and anywhere else the United States is unable to direct the domestic politics in distant lands, Romney would likely adopt much the same approach as the current administration.
Diplomatic Engagement: Had you listened to Obama in 2009, you might very well have concluded that he was out to change the world through engagement and diplomacy. But that was then. Obama has learned quite a bit, and appears to have come much closer to the tougher-minded Romney view on the merits of engaging Hugo Chávez, the Kim regime in North Korea, the mullahs in Tehran, and Bashar al-Assad in Syria. Conspicuously absent from this list of leaders that Obama has seemingly written off is Vladimir Putin, who appears to be an integral part of the White House's Iran strategy.
Romney has taken a much tougher line on Russia and China. Still, the realities of governing would invariably soften the Romney campaign line that Russia is public enemy No. 1 and that China is a currency manipulator.
Israel: Paradoxically, the one issue where Romney and Obama might actually differ is on the most bipartisan one of all -- Israel. Romney's views on Israel are guided more by his gut instincts (see Bush 43) than Obama, whose view of the Israelis is colder and more calculating.
The issue isn't support for Israel's security -- both would be committed to that. It's that damn peace process, which keeps turning up like a bad penny. Obama wants progress, and sees Prime Minister Benjamin Netanyahu as largely responsible for the lack of it. He may want to push some bold initiative in a second term, but it won't be so easy to do. For Romney, the peace process isn't going to be a priority unless the Israelis and Palestinians -- through violence or diplomacy -- make it one.
The bottom line? The new consensus is that the world's a more challenging place than ever, and both Democrats and Republicans are learning that we can't control it. (Of course, we never did.) That doesn't mean that the United States cannot lead or succeed in protecting its interests, it just means its leaders need to be more disciplined about how and when to project American power.
The new divide on foreign policy is clear -- and I, for one, am ecstatic about it. It's not between left and right, liberal or conservative, or Republican or Democrat. It's between making decisions that are smart, on the one hand, or dumb on the other. And I'm hoping that the next president -- whoever he is -- knows exactly which side America wants to be on.