Opinion: Sen. Warren's national child care proposal has an Obamacare problem

Sen. Elizabeth Warren (D-Mass.) has forced a conversation about child care costs. It is difficult to overstate just how important an issue this is for working families. Sixty percent of Americans told Pew Research Center they struggle to find affordable, quality care. And over the past few decades, weekly child care costs have skyrocketed 70 percent, while wages have remained stuck.