WASHINGTON (AP) — From the White House to the Vatican to the business elite in Davos, Switzerland, one issue keeps seizing the agenda: the growing gap between the very wealthy and everyone else.

It’s “the defining challenge of our time,” says President Barack Obama, who spotlighted the issue in his State of the Union address last month. A Gallup poll found that two-thirds of Americans are unhappy with the nation’s distribution of wealth. Experts say it may be slowing the economy.