Two incidents that occurred more than 1,000 miles apart on the same day recently illustrate the problems the United States faces in its efforts to halt drug smuggling.
In the small, affluent town of Topsfield, Mass., north of Boston, a state policeman -- scheduled to retire in December after 19 years on the force -- was arrested by fellow officers and federal agents as he reported for work.
He is accused of conspiring to smuggle 161/2 tons of marijuana into New England via a nearby fishing port in 1977. He is the second veteran Massachusetts state policeman alleged to have been involved in the distribution of marijuana in the past four months.
Meanwhile, in Miami, federal officials began gathering evidence and arresting dozens of persons indicted by a grand jury for conspiracy or other involvement in the smuggling of marijuana and cocaine into the United States from the Bahamas.
The latter incident attracted unusual attention because many of those indicted were active in professional stock-car racing, which, unlike other sports, previously was not connected with drug trafficking. Some are mechanics who allegedly used their knowledge of engines to keep the fast boats that haul the drugs ashore in top running condition.
The arrests and confiscations in Miami, which were the result of a lengthy investigation, came just two days after Vice-President George Bush -- in the same city -- had announced a series of new moves to crack down on drug traffic.
Mr. Bush said Hawkeye radar-equipped planes would be put into the fight off the south Florida coast. The Hawkeye, a smaller version of the AWACS (airborne warning and control system) aircraft, is especially adept at tracking low-flying planes -- one means by which drugs are commonly brought into the country. He also announced the appointment of a new US attorney for Miami and said the Customs Service and FBI staffs in the area would be beefed up by 130 and 43 agents, respectively.
But the antismuggling effort is a constant battle against an apparently ever more ingenious enemy.
Smugglers have been known to fly their cargoes into the US not only low and at night without using lights, but also so close to regularly scheduled airliners that the two planes show up as a single blip on radar screens.
And in New York recently, narcotics agents announced they had discovered that 115 pounds of heroin had been shipped to Newark, N.J., in expresso machines. The heroin was packed inside stainless steel containers whose lids had been sealed with wax to avoid detection by Customs Service sniffer dogs. The seizure was said to be the most important since the days of the so-called French Connection in the 1960s and early '70s.
Since the Reagan administration came to office 13 months ago, its major enforcement moves have included:
* Establishment of a task force on smuggling in south Florida, led by Bush.
* Giving the FBI ''concurrent jurisdiction'' with the Drug Enforcement Administration (DEA) in the antitrafficking effort, under FBI Director William Webster. Agents from each unit will undergo cross-training in the fundamentals of investigation practiced by the other. But the two agencies are not merging.
* Signing into law a bill introduced last year by Rep. Charles E. Bennett (D) of Florida that allows the regular armed forces to assist -- but not make arrests -- in the battle against smugglers. Discussions already are under way between DEA officials and representatives of the armed forces ''to figure out who's going to do what to whom,'' in the words of agency spokesman David Hoover.
In addition, federal officials have intensified their efforts to catch smugglers by tracking the huge amounts of cash they acquire, deposit, spend, or attempt to transfer outside the country.
These steps and others are not without their critics. Some in the DEA have complained that the joint effort with the FBI will dilute their agency and could spell ''the beginning of the end'' for it.
Sen. Joseph R. Biden Jr. (D) of Delaware, ranking minority member of the Senate Judiciary Committee, sees the FBI-DEA effort as only ''a half measure,'' says his press aide Peter Smith. Senator Biden identifies what he calls three major problems in the Reagan strategy: budgetary cutbacks for some of the units charged with antismuggling work, such as the Coast Guard; a lack of coordination between the FBI and DEA on the one hand and agencies outside the Justice Department, such as the State Department and the Customs Service, on the other; and a lack of new planning in overseas enforcement.
Biden and other Senate Democrats last year proposed establishment of a Cabinet-level post to coordinate all US antidrug efforts.
Rep. Bennett also complains that federal efforts do not go far enough. He is unhappy that, at Senate insistence, his bill was rewritten to forbid the US Navy to make arrests of suspected drug runners at sea. Only the Coast Guard has this power. He also says the federal task force focus should go beyond Florida.
The DEA places the retail value of illicit drugs supplied to the US market in 1980 - the latest year for which statistics are available -- at $68.5 billion to metric tons. The others, in order of street value, were domestically produced ''dangerous drugs'' like amphetamines and barbituates, and imported hashish, cocaine, and heroin.
Nearly 75 percent of the heroin reaching the US is from from Pakistan, Afghanistan, and Iran, says DEA spokesman Hoover. The rest is equally divided between Mexican and the so-called ''golden triangle'' of Southeast Asia.
But sizable new quantities of golden triangle heroin apparently are on the way. Mr. Hoover says no traces of the golden triangle heroin have been found in the US so far, although some has been seized in Western Europe. But ''we're very concerned,'' he says. ''We see it as a definite problem.''
The DEA spokesman says his agency, budgeted at $242.1 million by the Reagan administration for the 1983 fiscal year, isn't being undermined by cuts in federal spending. The money, he says, is $2 million more than the DEA had sought.
Other federal officials say that south Florida, which bears the brunt of drug smuggling, will be spared cuts in the Coast Guard and other law-enforcement agency budgets.