A full-fledged Democratic trade war has broken out."I love Elizabeth. We're allies on a whole host of issues, but she's wrong on this," President Obama said Tuesday night in an interview on MSNBC's Hardball with Chris Matthews, referring to liberal Massachusetts Sen. Elizabeth Warren.Warren and the progressive left, scarred by trade deals past like the North American Free Trade Agreement, or NAFTA, have launched a vocal fight against granting the president so-called "fast-track" authority to negotiate a 12-country Pacific trade deal. "Are you ready to fight?" Warren said at a rally April 15 with labor leaders and Vermont liberal Sen....