This could have been Michael Bloomberg's night. But instead it was his nightmare. Viewers were anxious for a first look at the billionaire former mayor of New York. And to meet or exceed them, Bloomberg had to do three things. Sadly for him, he failed at all three.

First, he had to establish a stage presence. But throughout the debate, Bloomberg seemed disengaged and withdrawn -- uncomfortable and emotionless. His performance improved a bit later during the debate. But for the most part, he seemed unable to project a vibrant persona, let alone charisma. And for a tough businessman, he seemed strangely hesitant, reserved and poorly equipped to push back hard on his opponents' charges of sexism, racism and capitalism.

Aaron David Miller
Aaron David Miller is a senior fellow at the Carnegie Endowment for International Peace, focusing on U.S. foreign policy.
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Second, he failed to make the case for electability Bloomberg seemed to make little of his potentially strongest talking point -- his capacity to beat President Donald Trump. This should have been his single most effective narrative, and he should have turned at least part of every question to that end. In the end, he remained a cardboard figure seemingly unable to outline what he actually stands for.

Third, he could not defend his most controversial policies. On stop and frisk, Bloomberg didn't offer anything remotely resembling a sincere apology as much as an explanation for why it didn't work. But the real damage which may well prove fatal to Bloomberg's campaign was his response to Massachusetts Sen. Elizabeth Warren's question: would he free women who had settled harassment or discrimination suits from their non-disclosure agreements so their accounts might be heard? Bloomberg refused, stumbled and fumbled trying to lawyer his way out of the dead-end in which he was stuck.

This article was originally published by CNN.