2. Boeing Co (NYSE:BA)
You mostly knew of its planes, but Boeing is also a major defense contractor. Unsurprisingly, Boeing’s major military products involve the sky, such as bombers, fighters (like the F-15), air tankers, drones, missiles, spy planes and even spaceplanes in the past. All that aircraft netted Boeing some $30.39 billion in defense revenues, which is amazingly only 32% of total revenues.

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