The good thing about a foreign company buying American real estate, such as Kennywood Park, is it can't move.

When foreign firms buy American icons it always triggers anxiety. It happened when Japanese firms bought California's Pebble Beach Golf Links and New York's Rockefeller Center in the 1980s, and it happened again yesterday when Madrid's Parques Reunidos said it was buying the beloved West Mifflin amusement park, along with local cousins Idlewood & SoakZone in Ligonier and Sandcastle Waterpark in West Homestead.

The sting is more acute because Kennywood is in the Mon Valley, which still reels from the loss of steel jobs in part to international competition a generation ago.

Match that with swelling nationalistic and anti-immigration feelings since Sept. 11, 2001, and it is the perfect atmosphere for a tidal wave of anger about the 101-year-old, family-owned national landmark's sale.

But fears about the sales of other American icons passed and so should they over Kennywood, said Barney Oursler, of the Homestead-based community advocacy organization Mon Valley Unemployed Committee.

For one, he noted, the park and its jobs cannot be shipped overseas. In industries such as steel, new owners may buy facilities with which they compete "just to put them out of business and stop the competition," he said. The Kennywood sale "is not one to be worried about on that" front.

Still, after dwindling for much of the 1990s, worries about foreign ownership of American assets have been surging again, fueled in part by China's rapid ascendance on the world economic stage and the outsourcing of factory jobs to developing countries across the globe.

Last year, Congressional complaints about a Dubai firm's planned takeover of operations at six U.S. ports quashed the deal, despite President Bush's support. And in 2005, Congress headed off purchase of Unocal, a middling U.S. oil firm, by a Chinese oil giant, China National.

According to the U.S. Treasury Department, foreign-owned firms employ about 5 million American workers, or 5 percent of the nation's work force. In this region alone, there are some 400 foreign-based firms, including giants such as GlaxoSmithKline, Bayer, Siemens and Sony, and they spend an estimated $1.4 billion annually in local wages.

Investment goes the other way, too. On Monday, for example, Pittsburgh-based PPG Industries got European approvals for the $3 billion purchase of a Dutch paints company.

But the Kennywood sale isn't just about international trade agreements. Things get more personal with generations remembering Potato Patch fries, family picnics and the mystery of the Racer.

"Our memories have been sold. To a company outside the country no less," Andy Hammar, a former steel worker from Clairton who is now living in Texas, wrote in an e-mail yesterday. "I know it was a business decision, but what a slap in the face to all the loyal Pittsburghers that made the park [and the family] successful over the years."

"What a shame that we keep selling off bits and pieces of America to foreign companies. And now a venerable family-owned amusement park. Hope the Henningers have fun counting their money," said Chris Hyatt, a 41-year-old graphic designer from Shaler. "Kennywood will never feel the same."

F.W. Henninger and Andrew McSwigan purchased Kennywood Park from the Monongahela Railway Co. in 1906 and the two families have remained owners since.

The sale smarts among many locally because of the old-fashioned nature of the park, which likely makes Pittsburghers feel more personally connected than they would to Six Flags, Disneyland or other corporate amusement parks.

Only Trimper's Rides in Ocean City, Md., and Blackpool Pleasure Beach in England have had longer family ownerships.

"At one time, most of the large amusement parks in the country were owned by families like the Henningers and McSwigans, but as corporate theme parks came to dominate, those families faded away. The Henningers and McSwigans were among the last of that breed," National Amusement Park Historical Association historian Jim Futrell wrote yesterday.

"Only time will tell, but the sale is the end of an era not only for Pittsburgh, but for the entire amusement industry."

There are also worries about losing another of the icons that make Pittsburgh special. While Kennywood cannot be uprooted from Pittsburgh, can Pittsburgh be taken from the park?

"Will our kids and grandkids know the Kennywood we have known," asked Matt Diersen, of Morningside, "any more than they will know where the 'Kaufmann's clock' is located?"

Kennywood officials insist nothing will change, and Parques Reunidos says it will keep the parks' administration in local hands.

But the sensitivity of the foreign issue was on many minds yesterday, including that of Kennywood spokeswoman Mary Lou Rosemeyer. During an interview at noon with WTAE-TV, Ms. Rosemeyer said, "We don't think it's going to become a giant taco stand." Her comments prompted complaints, leading Ms. Rosemeyer to apologize on a subsequent newscast later in the afternoon.