President Bush likes speed golf and speed tourism — this is the man who did the treasures of Red Square in less than 20 minutes — but here in the lake-studded capital of a nation desperately eager to connect with America, he set a new record.

Mr. Bush emerged from his hotel for only one nonofficial event, a 15-minute visit to the Joint P.O.W./M.I.A. Accounting Command, which searches for the remains of the 1,800 Americans still listed as missing in the Vietnam War.

There were almost no Vietnamese present, just a series of tables displaying photographs of the group’s painstaking work, and helmets, shoes and replicas of bones recovered by the 425 members of the command. He asked a few questions and then sped off in his motorcade.

It could not have been more different from the visit of another president, Bill Clinton, exactly six years ago this weekend, when he seemed to be everywhere.

And while the difference says much about the personalities of two presidents who both famously avoided serving in the war here, it reveals a lot about how significantly times have changed — and perhaps why America’s “public diplomacy” seems unable to shift into gear.

In 2000, tens of thousands of Hanoi’s residents poured into the streets to witness the visit of the first American head of state since the end of the Vietnam War. Mr. Clinton toured the thousand-year-old Temple of Literature, grabbed lunch at a noodle shop, argued with Communist Party leaders about American imperialism and sifted the earth for the remains of a missing airman.

On Saturday, Mr. Bush’s national security adviser, Stephen J. Hadley, conceded that the president had not come into direct contact with ordinary Vietnamese, but said that they connected anyway.