While renewed calls for a national focus on income inequality, predominantly grounded in a discussion of a minimum wage hike, are met with predictable squeals of “Class warfare!” from barons of industry, perched-on-high professional capitalists and other assorted defenders of the status quo, there’s an important second front in this developing battle — one that can be seen in the emerging populism of Senator Elizabeth Warren, who has made student loan debt (and the attendant profits reaped by federal government programs) one of her pillar issues. The new documentary Ivory Tower dives headlong into this thorny issue, not bemoaning achievement gaps or assaying the relative deterioration of American high schools and the public educational system, but instead asking pointed questions about what it is reasonable to expect from institutions of higher education, and how they may need to be retooled in the digital age.