The Elizabeth Warren vs Jamie Dimon feud is heating up by Chris Matthews @FortuneMagazine June 12, 2015, 1:20 PM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons There are few words in the English language that strike fear in the hearts of Wall Street bankers like “Elizabeth Warren.” The senior senator from Massachusetts has led the fight for tougher regulations on Wall Street, and she has an uncanny knack for marshaling public support for such an esoteric project. Jamie Dimon, perhaps America’s most famous banker, has a way with words himself. Earlier this week, the JPMorgan JPM CEO disparaged the leadership in Washington, singling out Warren in particular, saying: “I don’t know if she fully understands the global banking system,” according to a Bloomberg News report. On Friday, Warren fired back, saying on a Huffington Post podcast that: “The problem is not that I don’t understand the global banking system. The problem for these guys is that I fully understand the system and I understand how they make their money. And that’s what they don’t like about me.” This is not the first time that the two have sparred. Warren’s 2014 book A Fighting Chance describes several run ins with the JPMorgan CEO, in which they disagreed over banking regulations.