Warren takes aim at FedEx, Nike, Amazon in push for corporate tax hike

"What's happening right now in America, is these small businesses they pay their taxes at the full rate. They got to pay the whole thing," Sen. Elizabeth Warren (D-Mass.) told CNBC's "Squawk Box" Tuesday. "You look at businesses like FedEx and Nike. Businesses like Amazon and they pay zero. Right now there's a thumb on the scale in the tax part of this and that is a thumb to help the giants."