President Obama should nominate Elizabeth Warren to head the new Bureau of Consumer Financial Protection, and not only because of her credentials.

Ms. Warren — a bankruptcy expert at Harvard Law School, an Oklahoma native whose father was bilked of his savings by a business partner — developed the idea for the bureau in a 2007 article. Since then, as head of the panel that monitors the bank bailouts, she has become one of the nation’s most prominent consumer advocates.

There are other candidates, of course. What Mr. Obama needs to recognize is that this particular job, at this particular time, is about more than competence. As the reform bill went through Congress, the banks were unrelenting in trying to kill or weaken the bureau. Having failed, they want influence in selecting its director.

Meanwhile, polls have shown public mistrust or misunderstanding of the administration’s economic policies. Mr. Obama’s choice to head the bureau must demonstrate that he cares more about ordinary Americans than about Wall Street, that he understands that the public interest differs — sometimes sharply — from the interests of big banks. He needs someone the banks do not want, and that someone is Ms. Warren.

Bank lobbyists say a regulator like Ms. Warren would overreact in protecting consumers from abusive loans, constraining needed credit. That is unfounded. In her academic work and in the 2007 article introducing the idea of the bureau, Ms. Warren has shown that she understands the power of credit to do good.

But she also knows credit can wreak havoc. In 2007, she wrote: “For a growing number of families who are steered into over-priced credit products, risky subprime mortgages, and misleading insurance plans, trust in a creditor turns out to be costly. And for families who get tangled up with truly dangerous financial products, the result can be wiped-out savings, lost homes, higher costs for car insurance, denial of jobs, troubled marriages, bleak retirements, and broken lives.”

The banks don’t oppose Ms. Warren because she doesn’t get it. They oppose her because she does.