One of their favorite rhetorical tools in this and other social policy debates is to compare America, land of high tuition, to other countries that have publicly-funded free tuition. In a Washington Post op-ed from October of last year, for instance, 2016 presidential candidate Sen. Bernie Sanders argued: "In Finland, Denmark, Ireland, Iceland, Norway, Sweden and Mexico, public colleges and universities remain tuition-free. They're free throughout Germany, too. ... Governments in these countries understand what an important investment they are making, not just in the individuals who are able to acquire knowledge and skills but for the societies these students will serve as teachers, architects, scientists, entrepreneurs and more."

In other words: these countries are prepared to eat America's lunch economically because they are enlightened enough to have free public higher education.

Enrollment rates: Data from the Organisation for Economic Co-operation and Development indicate that the U.S. is tied for 12th out of 18 countries with available data when it comes to the share of citizens 25 and under that enroll in college, at 47 percent. Not so good, right? Especially compared to Denmark (56 percent) and Slovenia (68 percent) – two free college countries – that rank near the top. However, the countries nearest the U.S. – Germany (45 percent), Austria (47 percent) and Iceland (49 percent) – have free or very low tuition. And two countries at the bottom of the list – Sweden (40 percent) and Finland (41 percent) – offer free tuition. (The U.S. is ranked higher on the World Bank's measure of enrollment).

Attainment: Educational attainment tells a similar story. When it comes to the share of workers aged 25-34 who have finished tertiary education, the US is tied for eighth with Sweden, Switzerland and Israel at 46 percent. Korea (68 percent) and Canada (58), who both charge relatively high tuition, are at the top of the list. On the free college side, Ireland and Norway make the top six, but Finland, Iceland, Denmark, Germany and the Czech Republic finish behind America.