Are CNN anchors the grandest beings on the planet? On the other side of the Atlantic last week, as Pope Benedict visited the New Rome, I saw CNN's Wolf Blitzer introducing an item about the pontiff's progress; and, as the visual backdrop for the piece he had a gigantic picture of himself, a gigantic picture of the Pope, and a gigantic picture of the two of them shaking hands. “Hey,” Americans were asking each other, “who's that grey-haired guy talking to Wolf Blitzer?”

But his colleague, Lou Dobbs, makes Blitzer look like Estelle Morris. Not just an anchor, Dobbs is a brand. He is managing editor of his own show and an editorialiser of impossible gravity. Dobbs's themes are mostly populist and concern the betrayal of the American Dream and its small-town Dreamers, by the cosmopolitan, corporate elite, and their undercutting army of illegal immigrants. “The fear is,” he once informed his viewers, concerning reconstruction work being given to aliens, “that New Orleans will turn into La Nueva Orleans.” Pick the ironies out of that one.

I mention Dobbs because his ideas are important today, when Pennsylvanians are voting in the Democratic primary. One of Dobbs's earlier books - Exporting America - encapsulates the feeling in old manufacturing states that free-trade agreements have led to US workers' jobs effectively going to foreigners. This may seem strange walking down a British high street past McDonald's or Starbucks, or arriving home to turn on your IBM and opening Microsoft Windows, but it's how many Americans feel, and how Dobbs, who speaks as though he has never ventured farther afield than Key West, encourages them to feel.

My favourite headline of the past week was “Clinton, Obama attack each other for being too negative”. Particularly abrasive has been their accusation-swapping on free trade. According to Barack Obama, Hillary Clinton is soft on the 1993 North American Free Trade Agreement - involving the US, Mexico and Canada. “She says speeches don't put food on the table,” Mr Obama said in response to Mrs Clinton's stock critique. “You know what? Nafta didn't put food on the table, either.” It was a “bad trade deal”.

According to Senator Clinton's camp, although her husband was involved in getting Nafta passed, she was always iffy about it. No, say the Obamians, we have her on tape saying Nafta was good, as recently as 2004. Well, retort the Clintonites, we have Obama in the same year opining that US exports have “benefited enormously” from Nafta. “The fact is,” Mr Obama complained, “she was saying great things about Nafta until she started running for president.” And so was he, she replies.

One possible conclusion you could draw from this is that the 2004 Clinton/Obama was right, and that Nafta has been a good deal. This is what John McCain, who is not playing to the blue-collar audience quite yet, is free to argue. But on the streets, as measured by opinion polls, a pessimistic Middle America is less than sold on free trade.

Paradoxically - and in contrast to the cherished claims of anti-globalisers - it seems to be the citizens of developing countries who most value the opportunity to compete. I don't have much difficulty with the argument that free trade is better than protectionism, even for developed countries. True, one of the problems in the US has been a reluctance to understand that there would be casualties of globalisation there too, and to take steps to reskill parts of the workforce. This has permitted the populists to gain traction for their notion that, left alone behind implausibly secure frontiers, Americans would be richer than they are today.

Now, as the US Ambassador recently reassured worried Canadian businessfolk, this could all just be “political rhetoric” for election year. Certainly the differences are for show; a look at Mr Obama's and Mrs Clinton's Senate records shows identical voting histories on trade questions. And there have been suggestions that their advisers have been tipping the wink to foreign allies not to take all this stuff too seriously.

Certainly credulity was put under stress when Mrs Clinton's campaign spokesman said of her attitude towards Bill's 1990s Nafta-ing: “Like other married couples who disagree on issues from time to time, she disagrees with her husband on this issue.” In his recent memoir, Alan Greenspan, the former head of the Fed, recalled that President Clinton, inheriting the Nafta package from the first President Bush, made it his own. “Clinton argued... that you cannot stop the world from turning; like it or not, America was increasingly part of the international economy... He and the White House staff went all out, and after a two-month struggle they got the treaty approved.” This was no small deal, but a central aspect of the Clinton presidency.

But look, if they don't really mean it, what does it matter? As the ambassador says, chalk it down to campaign hyperbole. Except that such talk does have consequences, as we saw last week. Ostensibly, House Democrats had objected to the ratification of a trade pact with Colombia, because certain human rights issues had not been resolved. Since their first objections, it was generally agreed that the Colombian Government had significantly cleaned up its act. Then the Democratic Speaker of the House, Nancy Pelosi, announced that her majority party would still oppose ratification, because: “We're first and foremost here to look out for the concerns of America's working families.” Such a continental shifting of the goalposts was accompanied by as fine a hypocrisy as you will hear this year. “I do take this action with deep respect for the people of Colombia,” she said, “and hope, and will be sure, that any message they receive is one of respect for their country.”

Only if they are total idiots. Ms Pelosi took her stance despite an open letter from a number of former senior officials in Democratic administrations and Democratic members of Congress. They had pointed out the benefits of such a trade agreement and added that “to delay passing the US-Colombia FTA this year would send a negative signal to one of our closest allies in Latin America, and would be seized upon by our country's opponents as a sign of US inconstancy at a critical time”.

Words matter, especially when they foster an illusion about how the world is. Wrong speeches lead to wrong policy. In Pennsylvania the best Clintonite Democrat today is John McCain.

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