In a gold rush, you get rich selling picks and shovels. In an industrial boom, you can make a mint putting up buildings -- gigafactories for the makers of electric vehicles and batteries, huge warehouses for e-commerce, and hyperscale data center campuses for cloud computing and artificial intelligence. Over the last four years, Bob Clark's construction company, Clayco, has seen annual revenue nearly double, to $7.5 billion, continuing a run of explosive growth since its founding 40 years ago, when Clark was 25.

Still, Clayco's line of business has its share of perils. Booms go bust. Everything that can be built can get overbuilt. The future -- whether in the form of EVs or AI -- rarely arrives at the expected time.