Stock markets usually go up. Sometimes, they go away.

A fact of financial life that most investors have forgotten is that markets aren’t always liquid or continuous. They can dry up, or even die.

Of course, the Federal Reserve and other central banks have flooded investors with cheap money for more than a decade. So it’s easy to imagine that government policy will always prop up markets. Sometimes, it destroys them.

War is usually the culprit.

Trading was halted in major markets outside the U.S. for months or years at least 25 times in the 20th century, according to finance professors William Goetzmann of Yale University and Philippe Jorion of the University of California, Irvine. (Those halts, often associated with severe losses, don’t count the New York Stock Exchange, which closed in July 1914 to avert panic from the outbreak of World War I and didn’t reopen until that December.)

Many investors believe that markets are permanent and that profit is assured if you only hold stocks long enough. Earlier generations in Argentina, Chile, Egypt, Germany, Greece, Japan, Portugal and Spain, however, learned that governments can slam markets shut and keep them shut for a long time.

That’s why diversification is so important. Russia was less than 0.5% of total global stock-market capitalization and under 4% of aggregate emerging-market value as of Dec. 31, according to MSCI.

If you went all-in on Russia ETFs, you were still able to get out—at a price—at least for a while. On Friday morning, though, the NYSE Arca exchange halted trading in iShares MSCI Russia, Franklin FTSE Russia and Direxion Daily Russia Bull 2X Shares. The Direxion fund has already announced that it will liquidate on March 18. Trading in the other two available ETFs, VanEck Russia and VanEck Russia Small-Cap, could also be halted by CBOE Global Markets.

“With governments imposing sanctions and the market valued near zero, there’s really no place for retail investors to turn to trade Russian securities,” says Reginald Browne, head of ETF trading at GTS, a market-making firm in New York.

“You can’t sell, because you can’t trade,” says Dave Nadig, an analyst at ETF Trends. “For all practical purposes, these securities do not exist anymore.”

In theory, the Russia ETFs could hold out for a reopening of trading in Moscow. That would be a two-part gamble: Russia would have to honor their property rights and Russian shares would have to retain some value at that point. Rather than roll those dice, the funds are likely to liquidate and send investors back whatever cash they have left, say industry analysts.

Is there any chance that bets on Russian stocks might someday pay off?

Well, the odds aren’t precisely zero, but history can have a habit of hurting people when it repeats itself.

In 1911, Alfred Neymarck, a French economist, estimated that Russia was the fifth-largest investing center in the world, encompassing 5% of the global market for stocks and bonds.

More than 200 Russian companies were listed on the St. Petersburg Stock Exchange in 1914. Amid the havoc of World War I, it closed that year, reopening for two months in 1917. It shut down again after the Bolsheviks overthrew the Czar.

Trading didn’t resume for another three-quarters of a century.

Inside Russia, the market is frozen again.

Some Russian companies are listed on other markets. American share rights to Gazprom PJSC, the Russian energy titan, closed at $1.10 over the counter in New York on Thursday, down from $8.97 on Feb. 16. That price was 0.51 times its reported earnings per share over the past four quarters, according to FactSet. Sberbank Russia PJSC closed in the U.S. at 52 cents on Thursday, down from $14.76 on Feb. 16. That’s less than .2 times its earnings over the past 12 months.

Those aren’t typos: They are price/earnings ratios below 1.0. Companies’ shares normally trade at prices that are a multiple of their earnings. Russian companies’ earnings are now a multiple of their share price.

All this puts Russian President Vladimir Putin in position, if he wishes, to pull off one of the greatest and most brutal trades in the history of investing: With the market for Russian shares stymied, he could nationalize every major company in the country for kopecks on the ruble.

In May 1991, around the time it officially opened for trading, the chairman of what was then known as the Leningrad Stock Exchange told The Wall Street Journal he could foresee two futures for stock trading in Russia.

One, said Igor Kliutchnikov, was that the Russian market would become one of the biggest in the world.

The other? “I also have a pessimistic view: that we will return to the old distribution system—maybe they will call it a market system, but it will be the old one—and in this case, I see no need for our stock exchange.”

Years later, his first vision came true. Now the second one might.