The Global Risk Party's Missing Guest May Yet Show

A happy and uneventful year is winding to a conclusion with a series of records. Risk appetite is back, and an array of U.S. stock indexes have hit all-time highs. With investors gaining in confidence, the dollar has dropped, on a broad basis as measured by Bloomberg’s index, to approach its low for the Trump era, set in 2018. If it takes out that mark, it will be at its weakest in six years:

There are reasons for greater risk appetite, including the likely forthcoming approval of a second Covid-19 vaccine, from Moderna Inc., and growing confidence that congressional negotiators will thrash out a support package before Christmas for people harmed economically by Covid. But it is the appetite for risk itself that matters. If investors wanted to be more cautious, they could cling to brinkmanship in the Brexit negotiations, disquieting news that people receiving the Pfizer Inc. vaccine are suffering allergic reactions, disappointing U.S. economic data in the last few days, the growing antitrust storm surrounding Google and Facebook Inc., and the frankly terrifying news that a cyber-attack has managed to compromise several U.S. government agencies, including the one responsible for nuclear weapons. To look through that lot, people must feel bullish indeed.