Brent Saunders, the chief executive of Allergan, one of the largest pharmaceutical firms in the world, is concerned that in an era of increasing political polarization, Americans will become fed up and embrace the single-payer health care plan set to be unveiled Wednesday by Sen. Bernie Sanders, I-Vt.

He shared his candid thoughts last weekend at the Wells Fargo Healthcare Conference in Boston, a gathering for investors and major pharmaceutical and biotech firms.

Americans have lost trust in drug companies, Saunders said, noting the industry consistently ranks lower than oil and tobacco companies in public trust surveys.

“I think we’ve got to do things to bring that trust back,” the executive added, “because ultimately, someone’s going to be in the White House. Somebody’s going to be in Congress. Someone’s going to be somewhere and going to have to say, ‘Enough’s enough. Let’s just change the whole system. Let’s go to one payer. Let’s do something.’”

While single payer has been discarded as a fringe, far-left idea over recent generations, the policy proposal has gained new traction in the wake of the 2016 presidential election. Many in the Democratic Party are drifting to the ideas of Sanders and other progressives who have long advocated for expanding coverage by providing Medicare to all Americans.

Saunders observed that “the party that seems to be out of power tends to move dramatically to the left or to the right,” adding that the Republican Party during the Obama era had lurched more right-wing.

“We’re seeing almost the equal but opposite reaction here now that they’ve been swept out, the left of their party is really taken, gotten a louder voice and taken control,” Saunders continued, speaking about changes in the Democratic Party.