The ROI isn't 5 years, it's more that it won't generate any returns for 5 years and those returns might not pan out depending on policy change. If you build an American factory and right as it's getting up and running, the next administration rolls back all tariffs, you're left with massive debt and everyone undercutting your prices.
Risk. It's called "doing business". Anyone who has built anything great took risks because they had a vision and believed in it. They weren't "rent seeking" and looking for guaranteed returns.
