NAFTA a non-issue in the Denocrat Primaries?

As Democratic primaries heat up, with a key race in Pennsylvania on April 22nd, it seems that there is at least one trade issue that both Obama and Clinton agree on. In debates leading up to the Ohio primaries, Both candidates advocated the use of a potential opt-out of the North American Free Trade Agreement (NAFTA), if they could not renegotiate it to include stronger labour and environmental protections. The trade deal is extremely unpopular among Democrats in Ohio, which is facing economic challenges related to the US recession. In that state, NAFTA is blamed for thousands of job losses in the industrial sector. In fact, the only reason that NAFTA is being discussed in the U.S. primaries is that manufacturing jobs in the Northeast are suffering heavily under tightening economic conditions.
In a classic example of ‘playing up to the locality’, both candidates have reiterated their stance concerning NAFTA, anticipating the upcoming Pennsylvania primary. However there was no mention whatsoever of the agreement during campaigns in the Texas primary, where the benefits from trade with Mexico are well accepted. The play of political rhetoric has not gone unnoticed by the US northern neighbour. Canadian trade minister cautioned, in February that if the US decides to pull out of NAFTA, it might lose preferential access to Canadian and Mexican oil. The Obama campaign, which was especially outspoken was quick to reassure Canada, that this was mere “political talk”.
Republican candidate for the Presidential race, McCain assured the Canadians that he is a strong supporter of NAFTA. In fact he has used the Democratic skepticism of Trade liberalization to launch his own campaign rhetoric. “Democratic opposition to NAFTA could threaten Canada’s (large) contribution to the war in Afghanistan” McCain pointed out. However he may have a very good point. Every time in history that the US has practiced protectionism, a very heavy price has been paid for it.