Investors have short memories, and right now they are busy forgetting everything that supported the market over the summer.

Just a few short months ago, there was a twin argument for why U.S. equities were so high: First, the S&P 500’s defensive stocks provided ballast. Second, there is no alternative to stocks with bond yields so low (an argument so popular it has its own acronym, TINA). Those two factors kept markets near record highs, never mind the escalating trade war and the dire outlook for global growth over the summer.

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