It also made Michael Bloomberg a billionaire.

Now, I wasn’t being sarcastic in calling Bloomberg a great businessman. He is. And to his credit, he himself hasn’t, as far as I know, engaged in destructive financial wheeling and dealing. Instead, he got rich by selling equipment to destructive wheeler-dealers.

For those who don’t know what I’m talking about, I’m referring to the famous Bloomberg Terminal, a proprietary computer system that gives subscribers real-time access to large quantities of financial data. This access is incredibly expensive — a subscription costs around $24,000 a year. But it’s a must-have in the financial industry, because traders with Bloomberg Terminals can react to market events a few minutes faster than those without.

It’s an extremely profitable business. But is it good for the economy? No.

After all, does getting financial information a few minutes earlier do anything significant to improve real-world business decisions that affect jobs and productivity? Surely not. Bloomberg has, in effect, made his billions off a financial arms race that costs vast sums but leaves everyone pretty much back where they started.

Which brings me to Elizabeth Warren.

Warren stumbled badly, making herself a long shot for the nomination, by trying to appease supporters of Bernie Sanders. She endorsed proposals for radical health care reform that have almost no chance of becoming reality, and she was raked over the coals about paying for those proposals even though Sanders himself has offered few clues about his own plans.

But before all that, Warren had made a name for herself as a crusader against financial industry fraud and excess.

It wasn’t just talk. One key piece of the reforms instituted after the 2008 financial crisis, the creation of the Consumer Financial Protection Bureau, was Warren’s brainchild. Furthermore, by all accounts the bureau was wildly successful, saving ordinary families billions, until the Trump administration set about eviscerating it.

And here’s the thing: Financial reform, unlike health care, is an area in which it might make a big difference which Democrat becomes president. It’s true that other candidates — including Bloomberg! — have endorsed Warren-type reforms. But it is, I think, fair to ask how committed they would be in practice, and also whether they would squander their political capital on unwinnable fights, which is my big concern about Sanders.

Again, aside from the clear damage to Bloomberg, I have no idea how or if Wednesday’s debate will affect the Democratic race. But it may have helped remind Democrats that corruption, fraud and the excesses of Wall Street in particular can be potent political issues — especially against a president who is both personally corrupt and so obviously a friend to fraudsters.

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