Financial markets have finally been registering a grim reality. The coronavirus epidemic is likely to have more than a trivial effect on the global economy.

New ramifications keep appearing every day. Not only are global supply chains affected. Tourism is taking a big hit. Fewer people are booking cruises, and even business travelers are starting to think twice about nonessential air travel.

China is not only a supplier to Western manufacturers. China is a large source of global demand.

As the virus kept spreading, advance financial market indicators in Europe and Asia were down 3 or 4 percent.

U.S. stock markets until now have fallen only slightly, on the wishful premise that the Fed will bail out a faltering economy by cutting interest rates. But prepare for a big tumble. (As of 10:30 this morning, the Dow was down almost 800 points.)

Rates are already very low. While even lower rates are marginally good for the stock market, there is only so much they can do in the face of a slumping real economy (see: 2008 collapse).

A faltering economy would take some of the glow off Trump’s alleged economic success. He could say, of course, that the viral outbreak wasn’t his fault. But a president who takes credit for a strong economy that was mostly Obama’s doing has to suffer the blame for a softening economy largely made in China.

And to the extent that Trump shortchanged the Centers for Disease Control and Prevention, and did a head fake on a tough China policy but did nothing to bring supply chains home, he does bear some responsibility.

Americans wearing sanitary masks will not present an attractive campaign motif. This may stoke even more xenophobia (Make America Healthy Again), but the economic damage will be real, and viruses do not respect border walls.

Obviously, we have to hope that the epidemic will be contained. That seems increasingly unlikely. If the economic damage spills over onto Trump, there will be poetic justice in it.