Tech titans including Jeff Bezos, Elon Musk, Jensen Huang, Sam Altman and Tim Cook were among those invited to the event, hosted by President Trump and Melania Trump.

The president seems driven chiefly by the sense that A.I. is the way to economic growth, and nothing can be allowed to stand in its way.

Ms. Wiles, the first woman to be the White House chief of staff, had said in March that she had breast cancer.