The powerful stabilizing impact of the Federal Reserve’s COVID response is visible virtually across U.S. financial markets. What is most remarkable about this is how little the Fed has done to achieve these outcomes. To be sure, the central bank now holds $7 trillion in assets, an increase of $2.8 trillion since early March. Yet, virtually all the increase reflects large-scale purchases of government-guaranteed instruments. What we find astonishing is that the acquisition of risky nonfinancial debt remains tiny.

The point is clear: backed by massive fiscal support, the Fed’s mere announcement of its willingness to purchase corporate and municipal bonds, as well as asset-backed securities, has proven sufficient to stabilize markets despite the worst economic shock since WWII. Put differently, the Fed’s willingness to backstop markets has obviated the need to serve actively as a market maker of last resort.

In this post, we document these developments and then speculate about their implications. For one thing, in a future crisis where the U.S. fiscal and monetary authorities share key goals, people will now anticipate that the central bank will backstop financial markets. Because a central bank is almost certain to intervene when systemic risks rise, these stabilizing powers are welcome.

At the same time, the central bank’s backstop is a source of potentially serious moral hazard. We suspect that investors are now counting on Fed stimulus to support equity and bond prices (and possibly bank loans) even as household and business insolvencies rise. Yet, in a market economy, it is shareholders and creditors who ultimately must bear these losses. Indeed, were the U.S. equity market to plunge by 40 percent in the remainder of 2020, that by itself would pose little threat to the financial system, and ought not trigger large corporate bond (let alone equity) purchases by the central bank….