In the lead-up to Tuesday night's Democratic presidential debate, much of the back and forth on health care in the Democratic primary boils down to one theme: How can the country provide low-cost, high-quality health care to all Americans as quickly as possible? Of the four leading candidates — former vice president Joe Biden, former South Bend, Ind., mayor Pete Buttigieg, Senator Bernie Sanders of Vermont, and Senator Elizabeth Warren of Massachusetts — there is little distance between them on the desired outcome: universal health care and quickly.