Bankers tend to turn into gardeners when talking about the continuing dearth of mergers and other investment-banking deals. They mention “green shoots,” in the form of an acquisition here, or an initial public offering there, as hopeful signs of regrowth.

But this analogy might be too delicate for today’s world. Between the low-growth economic outlook, surging Treasury yields and wars in Israel and Ukraine, the risk isn’t just that the soil is a bit dry. It is that the ground is ripped up and parched, turning what is sometimes talked about as a temporary lull into one lasting for years.