... Bush and the first lady walked into the beaux-arts banquet hall, and Chilean officers, who appeared to be waiting for the moment, stepped in front of Trotta, blocking him from entering.

U.S. officials said Chilean police had been chafing for a week about a demand by Secret Service agents that they control the president's space, even when he was on sovereign turf. Now, it was payback time.

In the fracas that ensued, amid a flurry of half nelsons, one Secret Service agent wound up jammed against a wall. "You're not stopping me! You're not stopping me! I'm with the president!" an unidentified agent can be heard yelling on videotape of the mayhem.

It took Bush several minutes to realize what was happening. The president and the first lady walked on through the door onto a big red carpet, looking relaxed. They greeted Lagos and his wife, Luisa Duran. "You want us to pose here?" Bush asked Lagos with a grin, and they turned to face a wall of flashes.

Then Bush either realized he was missing something, or he heard the commotion. The president, who is rarely alone, even in his own house, turned and walked back to the front door unaccompanied, facing the backs of a sea of dark suits. Bush, with his right hand, reached over the suits and pointed insistently at Trotta. At first the officials, with their backs to him and their heads in the rumble, did not realize it was the president intervening. Bush then braced himself against someone and lunged to retrieve the agent, who was still arguing with the Chileans. The shocked Chilean officials then released Trotta.

Trotta walked in behind Bush, who looked enormously pleased with himself. He was wearing the expression that some critics call a smirk, and his eyebrows shot up as if to wink at bystanders.

Bush adjusted his right cufflink and muttered something to Lagos, took the first lady's arm and headed into the dinner of grilled fish...