Many U.S. industries encounter formidable foreign competition. Steel is an example. Because it is essentially a commodity, production and ship- ping cost differences cannot be passed on to buyers. Certain fixed costs for plants and equipment, incurred whether the company is operating or not lead producers during periods of lower demand to sell steel at a loss for a short time rather than shut down a plant. Where excess capacity exists in the short run, foreign firms may "dump" steel in the United States at prices below their costs. Services can also be dumped. Exhibit 8.2 is a summary of Senator Jay Rockefeller's (D-WV) testimony to the International Trade Commission urging that duties or tariffs be imposed on foreign producers selling below cost in the United States. In 2002, President Bush imposed steel tariffs that were ruled in 2004 to be in violation of World Trade Organization (WTO) agreements The political power of unions appears to influence the imposition of tariffs since industries with higher union coverage are more likely to have them levied against competitive goods produced offshore