He would walk north two miles, pausing in the bay of a deserted fire station in Greenwich Village to call a television station and urge calm. Three hours later he stepped into a press conference with Gov. George E. Pataki.

“Today is obviously one of the most difficult days in the history of the city,” he said softly. “The tragedy that we are undergoing right now is something that we’ve had nightmares about. My heart goes out to all the innocent victims of this horrible and vicious act of terrorism. And our focus now has to be to save as many lives as possible.”

Inevitably the question arose: How many lost? The mayor looked up through his glasses, aware that among the viewers of this live broadcast were the mothers, fathers, spouses, lovers and children of those who labored in the smashed towers.

“The number of casualties,” he said, “will be more than any of us can bear ultimately.”

That walk north, the spareness of his words and his passion became the founding stones in the reconstruction of the mayor’s reputation, transforming him from a grouchy pol slip-sliding into irrelevancy to the Republican presidential candidate introduced as America’s mayor. The former mayor has made this day the centerpiece of his presidential campaign, aware that millions of Americans hold that heroic view in their collective mind’s eye.

Political leadership is an uncertain alchemy, an admixture of the symbolic and substantive and the visceral. In times of consuming trauma, psychologists and historians say, a leader must speak with a trusted voice and sketch honestly the painful steps to safety. A leader must weave a narrative of shared loss while acknowledging consuming anger.