Warren Buffett famously does not invest in airlines. However, the airline index is up 35% over the past quarter. Is Buffett wrong about airlines? In this video, Brendan Byrnes says no. Among the significant structural barriers that prevent airlines from being good long-term investments are fuel, labor, and other operating costs, along with a lack of competitive advantage and the cyclical nature of the business. There may be short-term runs in airline stocks, but for the long haul, these aren't great companies to be had at fair prices. Check out the video for further details.

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