Sen. Elizabeth Warren (D-MA) listens as Consumer Financial Protection Bureau Director Richard Cordray testifies before the Senate Banking, Housing and Urban Affairs Committee in Washington, D.C. on Nov. 12, 2013. 
Photo by Win McNamee/Getty

Elizabeth Warren: Donald Trump is a ‘loser’

Updated

Let’s be honest – Donald Trump is a loser. Count all his failed businesses. See how he kept his father’s empire afloat…

Posted by Elizabeth Warren on Monday, March 21, 2016
A warning to friends and foe alike: Elizabeth Warren is ready to rumble.

The Massachusetts senator and progressive tribune has sat out the 2016 election thus far, forgoing a presidential bid herself and staying quiet about the candidates who chose to run. Last week, she signaled a readiness to re-engage in politics, and now, she’s made it clear she’s playing for keeps.

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Warren came off the bench Monday by unexpectedly injecting herself into the 2016 fray with a devastating barrage on Donald Trump that both played to her expertise and engaged in some of the very same kind of personal taunting and name-calling Trump is best known for.

“Let’s be honest – Donald Trump is a loser,” Warren said in the first of several messages on Twitter and in a message posted on her Facebook page, using a word Trump himself has often deployed against his enemies.

“Count all his failed businesses. See how he kept his father’s empire afloat by cheating people with scams like Trump University and by using strategic corporate bankruptcy (excuse me, bankruptcies) to skip out on debt. Listen to the experts who’ve concluded he’s so bad at business that he might have more money today if he’d put his entire inheritance into an index fund and just left it alone,” Warren wrote.

Warren was an expert on bankruptcy law before she ran for the Senate from Massachusetts in 2012. While Trump has become a favorite punching bag of Democrats, few have gone as far as Warren in calling him out personally.

She went on: “Trump seems to know he’s a loser. His embarrassing insecurities are on parade: petty bullying, attacks on women, cheap racism, and flagrant narcissism.”

“Many of history’s worst authoritarians started out as losers – and Trump is a serious threat. The way I see it, it’s our job to make sure he ends this campaign every bit the loser that he started it,” Warren concluded.

Warren is a famously cautious politician who avoids the press in Senate hallways and speaks out only on strategically chosen issues in strategically chosen ways to avoid diluting her carefully constructed brand.

The tweet storm, which was immediately greeted with cheers from the camps of both Hillary Clinton and Bernie Sanders, could be read several ways.

With Sanders’ path to the Democratic nomination slipping away, Warren could be reminding the faithful of whom the real enemy is (Trump, not Clinton). And she could be bolstering her position as one of the few figures outside of President Obama who can unify the Democratic Party after the primary.

She could also be trying to provoke Trump into a fight on her issue terrain. Or simply welcoming Trump to Washington, where he met with GOP leaders ahead of his press conference and speech to the American Israel Public Affairs Committee.

But one thing is clear: She’s reminding the world that she is here and a force to be reckoned with.

The Rachel Maddow Show, 3/10/16, 9:41 PM ET

Warren: Senate GOP 'paying the price for their own extremism'

Senator Elizabeth Warren talks with Rachel Maddow about how the past seven years of Republican anti-Obama extremism in the Senate has brought about the extremism in the 2016 Republican presidential campaign that now has Senate Republicans in a panic.

Warren is the only female Democratic senator not to endorse Clinton and one of only a small handful of Democrats in the upper chamber not to endorse.

Warren laid low for the beginning of 2016, waiting to give her first major interview after three months of near silence until March 10 to Rachel Maddow.

“I’m getting more involved, and I will get more involved as we head closer and closer to November. I’m watching what’s happening right now on the Republican side, and it reaches a point where silence is not a virtue,” Warren told reporters last week. “I’ll find a way. I usually have a fairly loud voice.”

Bernie Sanders, Elizabeth Warren and Hillary Clinton

Elizabeth Warren: Donald Trump is a 'loser'

Updated