Prologis (PLD -1.01%) is not only the largest owner of industrial real estate in the United States, but also the largest real estate investment trust, or REIT, of any kind. While the business itself is performing quite well, there are some fears regarding the state of industrial real estate as well as the interest rate environment, and these have caused the stock to fall by more than 20% from its 52-week high.Here's a rundown of how Prologis' business is doing, why the stock is down, and why it could be a g ...