Food safety is another convenient excuse. The EU still refuses to admit US beef to European markets for fear of negative effects on health caused by the growth hormones used. The real reason for the reluctance to admit that beef to European markets is probably that the American farmers produce more efficiently than their European counterparts. Human resources that could be much more productive in other industries are tied up in unproductive ones. Successful industries are harmed by the retaliation that protectionism provokes.
Protectionism is a lose-lose policy.
We should be under no illusion that poverty can be legislated away. Arguing against trade with India because of the use of child labour in that country means arguing against the economic development of India. Poverty can be fought with trade and development, not with sanctions. The only way to put a stop to the many bitter social injustices in the third world is economic development. Free trade can be an important tool for that, in fact free access to Western markets would be of greater benefit in real terms to the least developed countries than the development aid they currently receive.