Let's take a look at some of the key dates for World War II and how the U.S. stock market reacted.

The Dow Jones finished 1938 at 154.76.

3/16/39 - Hitler marches into Czechoslovakia. If we didn't take him seriously before, we had to now. Dow closes that day at 147.54. 3/17: 143.81.

9/1/39 - The Wehrmacht blitzes Poland. Dow closes at 135.25. 9/2: 138.09. After two days off for Labor Day*, the market rallies 7% to close at 148.12 (9/5). Unbelievable. By 9/12 the market hits 155.92. Warsaw falls on 9/27, Dow closes at 153.08.

*In these days the stock market was open Mon.-Sat.

11/30/39 --Finland invaded by the Soviet Union. Dow closes at 145.69

Market treads water over the winter as the world knows that Hitler will eventually make a move in the West. But first...

4/9/40 --Nazis land in Denmark (which immediately surrenders) and then quickly move into Norway. Dow is at 150.31.

5/9/40, the Wall Street Journal writes that an invasion of Holland "would awaken fears that England was about to be attacked." The next day, 5/10, two things happen. Winston Churchill becomes prime minister of Great Britain. Hitler swarms into the Netherlands, Belgium and Luxembourg, on his way to France. Dow was 148.17 on 5/9. 144.77 on 5/10 (a 2.3% decline). [Remember that with the time difference between the U.S. and Europe there was usually plenty of time for the U.S. market to react the same day].

5/12/40 was a Sunday. On 5/13, upon further reflection, the markets realized that all of this bloody action in Europe (coupled with Japan's Asian adventures) probably wasn't a good thing. The Dow falls 5% to close at 137.63. A few days later a Journal market column reports that "while numerous practical-minded individuals in Wall Street take the view that more intense warfare will be stimulating to our industries…they recognize the dangers inherent in a swift German victory." By 5/24 the Dow sits at 113.94…a 23% decline in two weeks (or about 2400 Dow points at today's levels).

On 6/3 and 6/4, the evacuation of 338,000 British and French troops from Dunkirk is under way. The Dow finishes at 115.79 on 6/4. 6/14 the Germans take Paris - Dow sits at 122.27.

The Battle of Britain takes place mostly between 7/31/40 (Dow 126.14) and 10/31/40 (Dow 134.61).

6/22/41 -- The Nazis attack the Soviet Union. The market is closed. On 6/23/41 the Dow closes at 123.97 (up from 122.51 on 6/21).

12/6/41 --Dow sits at 116.60.
12/7/41 -- Pearl Harbor, a Sunday.
12/8/41 -- Dow closes at 112.52 (off 3.4%).

By 4/28/42 the Dow has fallen to 92.92. From its peak of 155.92 on 9/12/39, the market has declined 40%. Or looked at another way, 39% from a level of 151.29 on 4/8/40.

Source for two quotes, Journal article written by Deborah Lohse, 1996

Brian Trumbore