If "Mr. Smith Goes to Washington" could become a movie classic, who knows what might happen to the drama called, "Mr. Jones Goes to New York," now playing at the American Stock Exchange in the financial district of Manhattan.

A little longer than one year ago, James R. Jones took over the starring role at the American Stock Exchange, often called the Amex. The 51-year-old Washington lawyer and former Oklahoma congressman became chairman of the Amex on Oct. 12, 1989, the day before the financial markets were hit by a mini-crash that took the Dow Jones industrials down 190 points in 90 minutes.

That episode was followed by the California earthquake, which knocked out the Pacific Stock Exchange. At the invitation of the Amex, which hurried up work on a new trading desk, two dozen PSE traders came to New York to buy and sell stocks from the Amex floor for several days.

That was followed by several fires that knocked out power, halted the computers and left floor traders twiddling their thumbs.

No sooner had these crises ended, when Jones found himself trying to figure out whether the Amex, along with other exchanges, should halt trading if they were hit by unconfirmed reports of a Persian Gulf war in mid-day. (The problem was solved when the shooting began at night).

But Jones also was confronted by sudden fears of terrorism and the need to beef up security at the exchange. (The problem was solved, in part, by adding guards and metal detectors and inspecting employees' handbags and briefcases.)

Even good news caused problems. Last Thursday, when the market took off like a Phantom jet, with double the normal volume, the Amex realized that the long months of dwindling business had left them with a curtailed clerical staff that might not be sufficient to handle a huge surge in trading. So the Amex had to quickly draft secretaries and other employees to help out when the crunch came.

All of these episodes prompted Jules L. Winters, an Amex executive vice president, to tell Jones recently, "When things turn around, you're going to find out that this is a great job."

Jones tells the story with amusement. Fortunately, he has a good sense of humor. And he will surely need it.

The American Stock Exchange, caught between the overwhelming prestige of the New York Stock Exchange and the steadily-growing clout of the electronic over-the-counter Nasdaq market, has been struggling to survive for a long time.

Moreover, Jones has come in to run the exchange at a time when the securities industry is in the fourth year of its own recession and has laid off 60,000 employees.

Up to now, Amex has managed to survive by expanding its product line. In addition to its common stock listings, Amex does brisk business in options.

A few years ago, it also added the Americus Trust investments called Primes and Scores. (Americus separates 26 stocks into their income-producing portion, or Prime, and their appreciation potential, called Score). They trade like ordinary stocks.

Recently, the Amex added puts and calls on warrants tied to the movement of the Japanese market's Nikkei index. They began to trade shortly before the Japanese market cracked, and the puts -- or bets that the market would fall -- were big winners.

Overall, the warrants accounted for 15 percent of the Amex's volume last year.

Jones said he plans to keep adding new investment products. But that raises an important question. At what point will all those new products turn the Amex into something other than a "real" stock exchange?

One Amex official suggests that the answer is to be found in a grocery store analogy. Would it be better for a grocery store owner to insist on selling only groceries, even if it meant that the owner went out of business? Or, would it be better for the owner to add other products that would help the store stay in business?

Of course, the latter course might mean that a grocery store would start to look a little like a shoe store, too. But so what, the official argued. Survival comes first.

In any event, Jones shows no signs of being doctrinaire. In fact, Jones recalled that when he was first approached about the job, he warned Amex officials he didn't have much technical expertise and also said, , "I might be a bit of an unorthodox thinker."

When he was later hired by the Amex board of directors, he said, he was given only one mandate. It was, he said, to "develop and implement a strategic plan to take the American Stock Exchange into the 1990s."

That, of course, is a tall order.

One small indication of the size of the problem is the price of a seat on the Amex. On March 31, 1989, a regular seat cost $215,000. On Nov. 16, less than two years later, the price of the seat was down to $87,500.

Despite being a stranger to the stock-exchange business, Jones's entry into Wall Street has been eased by his natural affability and his informal manner. Amex staffers say they have found it easy to get his attention.

Jones said he spent the first few months trying to convince Amex members "that the industry was changing very dramatically and they would have to be doing things differently."

Amex, he said, already has put together two joint ventures with Reuter, the news agency, for electronic trading, one an after-hours trading system, another for institutional-oriented trading.

Jones said he had gotten good cooperation from members of those ideas.

He also would like the change the corporate structure of the Amex, which is owned by its members and now functions somewhat like a farm cooperative, Jones said.

"My feeling is that there ought to be a way to restructure and streamline so that you can take advantage of new opportunities that might come up in the '90s," he added.

Jones said his strategic plan was based on two principles: "One we need to be customer-driven, and two, we need to be able to add value."

In the past, Jones said, the exchanges have been membership-driven and operated on the idea that, "What was good for the members is, hopefully, good for the customers."

"My view is that in the 1990s, that we have to be customer driven ... that what is good for the customer will be good for the members. And, unless we add real value to the service we give, there's no reason for us to exist."

Part of Jones's strategy is to try to set up a stock exchange operation in Hawaii to help in late-hour trading.

He also thinks that in the era when securities firms are trying to save money, an Amex-created company could furnish investment information to investors or could offer record-keeping services to securities firms.

And he may suggest ways for individual investors to use their personal computers to send orders to specialists on the Amex floor. Jones believes that the easier it is for investors to trade, the more they will trade.

To make many of these changes will require all of the political and negotiating skills Jones developed during 14 years active years in the House of Representatives. Trying to build budget coalitions in Congress was surely good training for trying to build coalitions among brokers, traders, retail and institutional investment institutions.

Jones, who is 51, might have spent his life as a journalist but he was offered a job in a congressman's office in Washington and that led, in turn, to a job in the White House in the Johnson years. Among the photos on Jones's office wall is a picture that was taken of Jones and his wife, Olivia, together with President and Lady Bird Johnson.

When Jones first came to Washington, he worked on the hill during the day and went to Georgetown Law School at night. A native of Muskogee, Okla., he got a taste of reporting while working on home-town newspapers. At the University of Oklahoma, he studied journalism and government.

After he left Congress, Jones joined the Washington law firm of Dickstein, Shapiro and Morin. The Jones family, which includes sons Geoffrey and Adam, are long-time residents of Capitol Hill. But they now also rent an apartment on the east side of Manhattan.