Discussion : Do trade restrictions evoke retaliation by trade partners, and how would this affect the gains from trade?

After listening to the audio clip WTO sides with U.S. in Poultry Dispute with China, consider the full impact of a restriction on trade such as a tariff. Do trade restrictions evoke retaliation by trade partners, and how would this affect the gains from trade? 

Use this link: http://www.wto.org/english/tratop_e/dispu_e/dispu_status_e.htm to begin your research on some of the trade disputes brought before the WTO. What is the nature of the claim, and does the action by the defendant impede free trade and therefore deserve scrutiny?