Im ready for a change I can believe in–specifically, for Barack Obama to back away from the protectionist rhetoric that has marred his presidential campaign.

Were about to enter the phase of our presidential season that might be called The Pivot. With both the Democrats and Republicans having settled on their presumptive nominees, the candidates will start trying to appeal to the independents who dont participate in the primary process.

Thats one reason why John McCain has talked about global warming in recent weeks: Conservatives remain skeptical of it, but other voters may want to hear him address the issue.

Ive looked forward to The Pivot for one simple reason: Democrats now have a chance rethink the harmful things theyve said about free trade for much of this year.

A few months ago, it got so ugly that when Senator Obama was scrambling for votes in Ohio, he talked openly about quitting the North American Free Trade Agreement. I think we should use the hammer of a potential opt-out, he threatened. At the very least, he promised to renegotiate this pact with our two most important trading partners.

This is madness. Every day, the United States, Canada, and Mexico trade more than $2 billion in goods and services. Almost 30 percent of Americas international trade is with these two nations. Since NAFTA was passed, our gross domestic product has grown by 50 percent and weve created 26 million new jobs.

Obamas attacks on free trade havent earned him much praise from the rest of the world, which is suddenly apprehensive about an economic isolationist taking up residence in the White House. It is very irresponsible, in my view, to pretend to people that we can disengage from international trade, warned Peter Mandelson, the European Unions trade chief.

The good news is that Obama is a savvy politician who knows that protectionism wont play everywhere. Last month, when he was campaigning in Indiana, he acknowledged a simple truth: Were going to have to trade.

Indeed, we are–especially when exports are a genuine strength in an economy thats showing signs of stress.

More recently, Obama has indicated that he really doesnt intend to wage a war on trade. In an interview with Fortune this week, he seemed to suggest that his attacks on NAFTA were too harsh. Sometimes during campaigns the rhetoric gets overheated and amplified, he said. Politicians are always guilty of that, and I dont exempt myself.

He has made other positive statements as well. I believe in free trade, he said on CNBC last week. As somebody who lived overseas, who has family overseas, Ive seen whats happened in terms of rising living standards around the globe. And thats a good thing for America; its good for our national security.

Unfortunately, the senator went on to bash trade that lifts corporate profits. You would think that hed realize that a lot of Americans actually work for corporations and own shares of stock in them. Still, this is progress. A logical next step might involve building upon his support of last years free-trade agreement with Peru and embracing a similar pact with Colombia.

At the very least, Senator Obama should start listening to what some of his fellow Democrats are saying.

Speaker Nancy Pelosi and the House of Representatives, writes former Carter administration official C. Fred Bergsten, have hamstrung U.S. trade policy and created the gravest threat to the global trading system in decades. Bergstens think tank, the Peterson Institute for International Economics, calculates that trade liberalization since the Second World War has enriched the United States by $1 trillion annually and that gains of another $500 billion per year are within reach.

Al From of the Democratic Leadership Council–an organization that helped propel the political success of Bill Clinton–also wants his party to reject protectionism. Globalization is here to stay. We need to respond with American ingenuity and optimism, rather than fear, he wrote recently. For important moral reasons that go to our partys first principles, Democrats should support efforts to expand trade. No American who works full time should be poor. Growing the economy and creating jobs remain the best ways to fight poverty, and neither is possible with a cocoon around our economy.

Thats sound advice–words that Barack Obama should come to believe in, before he tries to sell Americans a change that he hopes they can believe in.

Dean Kleckner, an Iowa farmer, chairs Truth About Trade & Technology.