Bush has long been an advocate for immigration reform, coauthoring the book Immigration Wars: Forging an American Solution last year in which he outlined his plan for comprehensive reform.
"It evidences a willingness to put the United States in a position to continue to be that beacon around the world," Napolitano said.
Napolitano, who now serves as president of the University of California system, named immigration reform as her largest failure during her time in public office, both as a secretary and governor of Arizona.
She said reform as failed because "the politics and cultural norms around immigration are so complicated, and the Congress right now is so ineffective, ineffective," she said. "But never give up."
The Senate passed a comprehensive package last year but it stalled in the House. President Obama has vowed, in the face of Congressional inaction, to use his authority to act on certain aspects of immigration reform after the midterm elections.