Could foreign policy be Bernie Sanders' undoing? Yes -- if you believe the polls

In the last Democratic debate before the New Hampshire primary, Hillary Clinton went on the attack against Bernie Sanders . The former secretary of state did so by focusing on the Vermont senator’s perceived weak spot: foreign policy.

Given that many voters seem to care a great deal about America’s role in the world, that could yet prove a fatal vulnerability.

Sanders, who polls predict will win easily in New Hampshire on Tuesday, appeared to be out of his depth when pressed about how his administration would handle foreign policy issues.

Two particular stumbles stood out. First, when asked about the presence of US ground troops in Afghanistan, Sanders replied: “We can’t continue to do it alone.” America isn’t alone in Afghanistan, where the Nato coalition is still present; Sanders’ answer was far more relevant to US troops in Iraq.

Second, when asked whether North Korea, Iran or Russia posed the greatest threat to the US, Sanders said Islamic State did. Pressed further, Sanders said North Korea, “because it is such an isolated country run by a handful of dictators, or maybe just one”.

Clinton’s vote for the Iraq war – when she was a senator from New York – could also leave her vulnerable but the former secretary of state was quick to shift the focus back to Sanders’ inexperience, saying: “When New Hampshire voters go on Tuesday to cast your vote, you are voting both for a president and a commander in chief.”

But does foreign policy even matter to those who were watching the debate and making up their minds?

In short, yes. It might even be fair to describe foreign policy as the defining issue of this election, if public polling from Pew Research Center is to be believed.

In December 2011, US adults were asked about the most important issues facing the country on the eve of the 2012 election: 55% mentioned economic concerns and only 6% mentioned foreign affairs.

When Pew offered the same options to respondents in December 2015, only 23% chose economic concerns – and 32% said foreign affairs.

More specifically, terrorism is a growing issue. In December 2014, just 1% of respondents said terrorism was the most important issue facing the country. A year later, that had risen to 18%.

There are, however, clear partisan divides here. Republicans are much more likely than Democrats to say that Iran’s nuclear programme, the Israeli-Palestinian conflict and China’s power are the top threats to national security. Democrats are almost as likely to consider global climate change a national threat as Isis.

Unless Sanders can build confidence in his ability to handle foreign policy (or convince Democrats that the economic issues which form the centerpiece of his electoral platform are the most pressing facing the country) his efforts to reach the White House may well be in trouble.

The latest polls

With the New Hampshire primary just three days away, a poll from CNN and WMUR published on Monday morning is particularly interesting.

The survey is based on interviews with 837 adults in New Hampshire before the Iowa caucuses and 556 adults after them. Not all the individuals questioned said they planned to vote in either party’s primary, and the margin of error on these numbers is over 5%. In other words, be cautious interpreting these numbers.

The poll suggests Sanders has not been harmed by his very narrow defeat in Iowa. The Senator could win 61% of support in New Hampshire; Clinton is backed by just 30% of possible voters.

Those numbers are largely consistent with the averages Real Clear Politics creates across dozens of polls, which also suggest that Sanders has a 31% lead.

Another poll, from NBC/WSJ/Marist and published on Thursday, tells a slightly different story. The 2,551 adults interviewed 2-3 February gave Sanders a 20% lead on Clinton.

Finally, a survey from the Lowell Center for Public Opinion suggests the race is even tighter, with just 15% between the two Democratic candidates.

Among Republicans, polls published since the Iowa caucus suggest a slight dip in support for Donald Trump, but not enough to make a dent in his considerable lead in the state. An average of all polls currently suggests Trump is 17% ahead of his closest rival in the state, Marco Rubio. The Florida senator overtook Ted Cruz two days ago – a trend that might yet be reversed.

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