The writer defines the two terms according to the
paper "Protectionist Trade Policies: A Survey of
Theory, Evidence and Rationale"
by Coughlin, Crystal and Wood. The
paper notes that the liberal
theory was made popular by the works of Adam Smith, and the concept of protectionism is at the root of the recent trading blocks such as NAFTA, EU, ASEAN and SEATO. The paper attempts to discover which theory is most successful in the real world.