GLEN ARBOR — The idea of permanently protecting exceptional lands for public enjoyment began in 1872, when President Ullysses S. Grant established Yellowstone National Park, the first of its kind in the world. National parks are, in effect, a public estate, a pact between a nation and all its people, and are among the purest manifestations of American Democracy.

Never, though, has this noble idea come under sharper attack than it has over the last eight months in the Sleeping Bear Dunes National Lakeshore, the lower peninsula’s only national park. The assault began last December, when Robert A. Kuras, owner of The Homestead Resort in Leelanau County, and two board members of Friends of the Crystal River, a local environmental group, made a surprising announcement. A compromise had been reached in a fierce, decade-old struggle over Mr. Kuras’s plan to fill in wetlands and develop a golf course along a free-flowing reach of the Crystal River.

Under the proposal, Mr. Kuras would receive 204 acres of the 71,000-acre Sleeping Bear Dunes National Lakeshore, room enough to build an 18-hole championship golf course, a clubhouse, and private homes. In return, Mr. Kuras would give his 161 acres of marsh and woodland on the Crystal River to the National Park Service.

Mr. Kuras was initially successful in portraying the swap as a useful compromise that would advance the public’s interest in protecting the river and enhance his resort’s economic future As a result, the swap was immediately endorsed by, among others, the Legislature, Governor John Engler, and Lt. Gov Connie Binsfeld. Republican Senator Spence Abraham quickly wrote legislation to put the swap into effect. Newspapers, local business leaders and even some townships also jumped aboard.

To be sure, a successful swap would have resounding economic benefits for Mr. Kuras, who would gain control of a breathtaking stretch of woodland and meadow with magnificent views of Lake Michigan.

But as Interior Department officials and other critics more closely examined the proposal the ominous ramifications to the national interest were revealed. According to current and former Interior officials, the plan to trade private land for public land within the Lakeshore had no "demonstrable benefit to the nation," which is a requirement of land exchanges involving a national park. In almost every way, the trade was structured to benefit a single individual, they said.

In addition, the swap appeared to violate the 1970 enabling legislation that established the National Lakeshore, and had no precedent in the 124-year history of the national parks.

Most importantly, said Stewart L. Udall, Secretary of the Interior during the Kennedy and Johnson administrations, such a swap would allow for the whittling away of valuable lands from the national parks, and would undermine the credibility of the entire national park system.

Why? Because in establishing the Sleeping Bear Dunes National Lakeshore and every other national park, the U.S. Government deployed its Constitutional power of condemnation, permanently securing land in the "public interest" for "public uses." Opposition to the condemnations was so strong in Northwest Michigan during the 1960s and 1970s that the Sleeping Bear Dunes National Lakeshore was among the most difficult parks to establish, said Mr. Udall.

Building an exclusive championship golf course and luxury homes on previously condemned land within the National Lakeshore is a legal stretch, at best, of the public use doctrine, according to the park service. In addition, the precedent set by the swap would make it harder to establish new parks and enlarge existing ones, since property owners could argue that the federal government may not be taking their land for a public purpose.

"This is an attempt to set a bad policy that is not in the national interest," said Mr. Udall, from his home in Santa Fe, N.M. "This is a sellout to a fat cat."

Months after the swap was proposed, that message has finally reached Northwest Michigan and Washington. Two townships rescinded their support. And earlier this month, Democratic Congressman Bart Stupak, who represents Leelanau County, publicly announced his formal opposition to the plan, effectively killing the idea in Congress. "I think it is wrong to take land held by the National Park Service and give it to a private developer," Stupak said.

A spokesman for Sen. Abraham, sensing the political winds have turned, acknowledged that the Federal legislation has been withdrawn. For his part, Mr. Kuras declined to respond to several requests for an interview.

Now that the swap plan is dead, public attention is returning to safeguarding the Crystal River. The Northern Michigan Environmental Action Council, a volunteer citizens group, prepared a study this month that recommends three alternatives, including public purchase of Mr. Kuras’ riverfront property.

Still, the bad odor of the proposed deal still lingers. In essence, the Homestead swap threatened the central tenet of the national park ideal. Since 1872, as a matter of public policy, the United States has protected its most magnificent and unique natural lands for the permanent enjoyment of all citizens. Trading such an ideal away for the benefit of a resort owner would make a mockery of a National Parks System that has a notable history and enormous popular support.