A JAPANESE tycoon named Minoru Isutani has just received approval to make California's exclusive Pebble Beach Golf Links even more exclusive. Mr. Isutani, who bought Pebble Beach last year, plans to sell 1,500 lifetime memberships in the Pebble Beach National Club for as much as $750,000 each. Members - most of whom are expected to be Japanese - will be able to reserve tee times up to five years in advance. Only the last hour of tee time each day will be available to the golfing public.From an economic standpoint, Isutani's plan makes sense: Someone has to pay off his $830 million mortgage on the property. And even before he assumed ownership, the closest most Americans ever got to the famed links was via televised tournaments, where cameras tease viewers with shots of windswept cypresses, emerald fairways, and rolling surf. Even so, anyone willing to pay $200 for a round of golf could still tee off among the rich and famous - a policy that promoted at least an illusion of public acces s. Now, with Isutani's victory, another gate appears to be closing on one of the most scenic stretches of coastline in the United States. As Diane Landry, a staff attorney for the California Coastal Commission, said in opposing the plan, "The golf course isn't going to get any bigger and the day isn't going to get any longer, so private members will push out the public." Pushing out the public is a pattern equally evident on some of Florida's most beautiful beaches. Tourists and local residents who once enjoyed nearly unobstructed views of white sand and aquamarine water now find those views blocked along beachfront highways. Expensive high-rise condominiums form stucco fortresses that extend for miles, forcing everyone but their well-to-do occupants to head for crowded municipal beaches. The few waterfront lots that remain undeveloped sport distinctly unfriendly signs: "Private.Keep Out.No Trespassing." Does all this exclusion signal a growing drawbridge mentality - an attitude that says, "Let me in but keep everyone else out."? Charles Murray, writing in the National Review, predicts that in the relatively near future the rich will constitute between 10 and 20 percent of the American population. Whatever good accompanies this rising economic tide, Mr. Murray cautions, might be diminished by "its potential for producing something very like a caste society, with the implication of utter social separation that goes with that most un-American of words." As evidence of a "secession of the successful," he points to the increasing popularity of the "gated community." Environmentalists eager to save the world warn about endangered species and fragile ecosystems. But preservation involves more than not chopping down a redwood or bulldozing a rain forest. In its broadest sense, it can also mean preserving a measure of public access to scenic areas, coastlines, and even that most taken-for-granted commodity, sunshine. Here and there, a few success stories offer hope for a more egalitarian approach to development. The Massachusetts legislature has voted to limit future construction of tall buildings that would cast shadows on Boston Common. A lawyer representing a group called Friends of the Public Garden and Boston Common calls the Common "one of the most significant open spaces in the country. To risk losing its value because nobody did anything would be a tragedy." Similarly, the Cape Cod Commission seeks to become a model of land-use planning and regulation. Describing its powers as "very strong," the group wants to "ensure that the Cape Cod we leave our children is the Cape we would hope to leave them." Preservation versus "progress." Public interests versus private rights. The conflicts present difficult choices for Americans accustomed to play now and pay later. But if the "land of the free" is to keep some of that land accessible in the future, can short-term impulses always take precedence over long-term planning? Can "posterity" continue to be a word that gets lip service but often little else? The era of innocence has passed when Americans could sing, "The best things in life are free." But if the wind blew through the Pebble Beach cypresses in a certain way, the ghost of another old song might be heard above that golf course: "Don't fence me in."