Warren’s unbridled bellicosity Wednesday night offered an unconventional answer to that question. Some saw her performance as an act of desperation: a flagging candidate seeking discount media coverage with a parade of quotable moments. Or it may have been more strategic: driving a stake through the heart of the revenant stop-and-frisk architect, as a televised show of devotion for progressive and black voters. Either way, as countless postdebate write-ups have already pointed out, it was a return to the “fighter” identity that Massachusetts voted for in 2012. But that’s underselling its novelty.