TALK IS CHEAP, particularly when it comes to dealing with this nation's growing problem with the "recreational drugs," marijuana and cocaine.

Taking serious action, on the other hand, would be quite costly -- in monetary terms if you began to fight a real criminal war against the traffickers around the country, or in political terms if it were decided to decriminalize one or both drugs.

Recall for a moment the days of Prohibition.

"Because of the Prohibition issue, liquor was on everyone's mind. People were curious, and drinking was more attractive now that it was illegal. Saloons quickly reopened as speakeasies, supplied with liquor by underworld dealers and protected from arrest by corrupt police and public officials. Bootlegging became a vast enterprise controlled by murderous gangsters, who divided territories among themselves, settled their differences with guns and bribed public officials by the bunch."

That's the Encyclopedia Americana's simplistic description of the era of the Roaring Twenties, from 1919 to 1932, when drinking liquor was illegal. By substituting drugs for liquor, however, the paragraph easily could describe the situation today, including the appeal to the professional class of doing something illegal, the business role of violent criminals in supplying drugs, and their corruption of police and public officials in the process.

Prohibition represented a bad compromise between political pressures to do something about drinking and the facts of life. The Reagan administration is also caught between conflicting pressures on the drug issue, and judging by its recent, inconsistent public statements, it has found some rhetorical gimmicks to attack the drug problem, but no concrete steps that might effectively deal with it.

The administration's ambiguous stand was reflected in President Reagan's Oct. 2 radio broadcast, which was devoted to his new strategy on drugs, and then the White House briefing three days later where his aides gave the outlines of what the Reagan strategy really entails.

If I were a trafficker or user of drugs, the President's stirring words that he was "going to duplicate the south Florida experience for the entire United States" might give me some concern. After all, the government's south Florida joint task force had mobilized an impressive military force to cut down on smuggling and backed it up with almost 300 additional Drug Enforcement Agency and Customs personnel (although they were borrowed from other offices around the country, not added as new personnel).

But three days later the White House aides made it clear how little the federal government was going to do to fullfil the President's grand words. And I was reminded of how often over the past few weeks, during interviews on drug problems in Florida, Georgia, North Carolina and here in Washington, officials brought up the sad experience of their predecessors who had to try to enforce Prohibition.

I learned a lot in these conversations, both about the widespread nature of drug use and the enormous amounts of money it is generating, and the effect it was having on the people attempting to control it.

George Garrison is a lieutenant in the Athens, Ga., police department in charge of the drug squad -- a euphemism that covers Garrison and a handful of other policemen working for him. He sat in his office -- a bare room in the basement of the two-story building that houses the Clark County district attorney -- dressed in fatigues, waiting to hear from one of his colleagues who was out trying to make contact with an informant.

Confessing he was outmanned, out- equipped and clearly out-financed by the drug dealers, Garrison brought into the discussion another factor -- his standing among his peers in the community. He was particularly interested in two contemporaries from his high school days 20 years ago in Athens who had since turned to illegal activities, one running a gambling operation the other dealing in drugs.

They both enjoyed notoriety and even admiration in the community. And while Garrison struggled financially to raise his family, they were running around town in Lincoln Continentals, hanging out at nightclubs and restaurants, and flying off to Florida or Colorado to work and play with their high-living friends. In effect, he was saying, it appeared to him that he -- the cop -- was the outcast from society's mainstream, not these two former friends living outside the law.

Then there was Rufus Edminsten, once Sen. Sam Ervin's aide on the Senate Watergate Committee and now the politically-ambitious attorney general of North Carolina. He talked about the inroads that the drug business is making in his state and the money it is producing. Unemployed dockworkers at the port city of Wilmington, N.C., are offered $10,000 for one night's work, off-loading boats that have brought marijuana up from the Bahamas or Jamaica or all the way from Colombia.

But the latest trends may be better indicated by the new activity in the northwest mountains of the state, where live the families that once made mooshine liquor. According to Edminsten, these folks are now deep into sophisticated cultivation of marijuana, planting and harvesting a leaf that is described as far more desirable to American users than that which they had been getting from outside the country. And, Edminsten noted, they were making far more money from raising the drug than they ever had from making liquor.

In Florida, the stories were much grimmer, for in Miami, heart of the country's "recreational drug" trade, violence is a way of life. There, a 10-year-veteran of the Drug Enforcement Administration sat in a sophisticated restaurant one night and looked around at his contemporaries, all well-paid and well- dressed, drinking and smoking pot and -- he speculated -- chatting about the state of the drug trade.

Finally there was the long-time drug enforcement official who is about to retire. He's worked in drugs for years, during periods of public indifference to the illicit trade, when people only got excited if the villians were Mafia heroin pushers. He's seen the use of recreational drugs far surpass heroin, and watched the money involved go from the hundreds of millions into the tens of billions.

He now is caught up in what he describes as one of the more cynical political operations of his career. The talk is about a major war on drugs, but the activities undertaken, he says, will have little long-term effect. The joint task force will make a dent on the amount smuggled into the country this year, the increased enforcement will lead to more prosecutions, but without any assurance of convictions. And unless the south Florida task force becomes permanent, he said, with additional personnel and forces deployed to those areas of the country which now have depleted ranks, nothing will really change.

All of which brings us back to the President's message and his aides' explanation.

"We're undertaking a narcotics policy that might be termed, 'hot pursuit,' " the President said. "We're not just going to let them go somewhere else; we're going to be on their tail."

It sounded great, but turned hollow in the mouth of Assistant Attorney General Rudolph W. Guiliani three days later. When asked whether the numbers of DEA or FBI agents were going to be increased, Guiliani said, "That's something that always has to be looked at. . . . But at this point there's no need for any kind of dramatic increase."

If you don't put more people in the fray, how do you carry out the President's notion that his administration was going to "duplicate south Florida" and enter into "hot pursuit"?

The short answer, apparently, is that you can't. Guiliani told newsmen on Oct. 5, the Florida task force was set up to meet "an emergency situation" that was unique. "Although we do have some very difficut situations, there's nothing quite on the level of south Florida," the Justice official said. This apparently signals a cooling off of "hot pursuit."

"We're not going to end the problem of drugs," added Guiliani. "What we're hoping to do is to get it under greater control in the situation that we inherited."

The main tools apparently will not be the costly equipment and personnel that were highlights of the joint task force effort, but rather something less expensive: "emphasizing the educational aspects" of reducing drug use, as Guiliani put it.

Enter Nancy Reagan. She appeared with the president on his Oct. 2 radio braodcast to report on her trips around the country talking about drugs. "Few things in my life have frightened me as much as the drug epidemic among our children," she said.

She called the "parents' movement" a positive sign, and the White House aides took up that theme.

"We are calling for a 30 percent reduction in the daily use of drugs amongst high school seniors," proclaimed Dr. Carlton Turner, the White House drug expert. This will be accomplished by Washington supporting "the parent group concept as a workable approach whereby each parent will be actively involved," Turner said.

Who is going to get the parents to cut back on their drug use is a question Turner did not address.

To one dejected drug enforcement official, the "Reagan administration like others before it just cannot make up its mind on what to do about drugs -- enforce the law or change. Until they do it's going to continue just like Prohibition," he said, "with the corruption and violence and the decline of public values."