Final answer:
Political support for economic integration through trade is largely based on the success of free trade ideas and the formation of trade agreements and economic unions to promote liberalized trade.
Step-by-step explanation:
Two political factors that support the idea for economic integration of nations through trade are the belief in free trade ideas over protectionism, and the political decisions to enter into trade agreements and economic unions. The global move towards free trade marks the success of economic principles over opposition forces that favor protectionist measures, such as industries without a comparative advantage. Political commitments are demonstrated by joining regional trading agreements and wider global organizations like the World Trade Organization, which promotes the idea that countries can achieve material gains and economic growth through trade liberalization.