1) Protection of one domestic industry can harm another if it limits international trade. For example, protecting US steel may help steelworkers but hurt manufacturers that rely on steel as an input.
2) Comparative advantage is more important than absolute advantage for trade because it considers opportunity costs. A country is better off specializing in industries where they have lower relative production costs rather than trying to produce all goods domestically.
3) The discussion highlighted how considering total costs and comparative advantages can lead to greater profitability compared to focusing only on short-term cheaper options. This lesson about taking a broader view can be applied when making management decisions about budgets and investments.