What happened

It's Wednesday, and aerospace stocks are a shambles.

Actually, most stocks are having a pretty bad day, with the S&P 500 falling as far as 2.7% at 1:35 p.m. EDT today. But aerospace stocks are doing even worse. Shares of Boeing (NYSE:BA), for example, have fallen 5.5%. General Electric (NYSE:GE), which gets more revenue from the sale of jet engines than from any of its other businesses, is down 6%. Even start-up space tourism company Virgin Galactic (NYSE:SPCE), which isn't actually doing much of anything just yet, is still down a sizable 4.9%.

3 red arrows going down and crashing through the floor

Image source: Getty Images.

So what

There is really no bad news from any of the three companies themselves. To the contrary, Reuters recently wrote that Boeing is on track to begin a key flight certification test that could help put its 737 MAX back in service, as early as next week. So we need to look to macroeconomic news for a reason. And two answers seem most likely.  

First and foremost are the latest coronavirus statistics: 9.3 million patients infected with COVID-19 worldwide, with 2.35 million in the United States. There were 5,000 new infections reported in a single day in Texas. And across the nation, more states reported an acceleration in the spread of the virus than reported a successful flattening of the curve.  

Because an uncontained virus is a health risk for anyone leaving the front door, none of this is good news for travel and tourism demand. Unless we get the coronavirus under control, it's likely to cut short the revival in air travel, depress demand for new airplanes (Boeing) and new jet engines (GE), and stifle demand for novel ways to fly (Virgin Galactic).

Adding to investor worries, there's word now that the Trump Administration is contemplating $3.1 billion in new tariffs on European trade goods, a tit-for-tat response to EU plans to tax digital transactions of U.S. tech companies like Facebook, Google, and Amazon.com. Rightly or wrongly, the president's plan opens up the potential for Europe to respond in kind with tariffs of its own on U.S. trade goods.

Now what

Given how stressed aerospace companies are already, and the high profile of Boeing and GE, I wouldn't be surprised if those two companies bear the brunt of European sanctions. Such a move would, after all, serve the dual purpose of both responding to U.S. sanctions, and at the same time help to protect a fragile European aerospace sector from competition from Boeing and GE -- probably a politically popular move in Brussels at a time like this.

And there you have it, folks: Coronavirus plus a brewing trade war with Europe are adding up to drive down the value of U.S. aerospace stocks today. For them to move back up again, I suspect we're going to need to see either renewed progress on the coronavirus, or a lessening of trade tensions with the EU.

Until one of those two things happens, expect the stock market to remain cantankerous.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.