Borrowers, whether they’re the government or individuals, should focus less on potential returns and more on risk management, writes Allison Schrager. “As long as the world is uncertain, there is no such thing as good debt or bad debt. There is only good risk management and bad risk management. It’s a crucial concept to understand as the US continues to add to its public debt, which has tripled in the last two decades to almost $36 trillion.”