ONE OBVIOUS reason President Obama should pick Elizabeth Warren to lead the Consumer Finance Protection Bureau is that the new agency was her idea to begin with. Created as a unit of the Federal Reserve by the recent financial-reform bill, the agency will have the ability to set rules for credit cards, loans, and other financial “products’’ that banks and similar institutions offer to consumers. It needs a leader who has a passion for protecting consumer interests — and who recognizes that doing so contributes to the health of the financial system. Warren is easily the best candidate for the position.

Warren, a Harvard Law School professor, has conducted extensive research on bankruptcy, predatory lending, and other consumer-finance issues. Throughout her tenure as head of a panel appointed by Congress to provide oversight of the federal bailout funds, Warren has sought to connect the machinations of the financial system with the struggles of average families. She raised early alarms about subprime mortgages, and her work casts light on how a deliberate obscurity in the terms of credit cards and mortgages contributed to an unsustainable growth of consumer debt.

Her activism over the years has contributed to fears on Wall Street that the consumer-protection agency she inspired will create a vast new regulatory burden. And to be sure, the regulatory system shouldn’t discourage financial innovations that promote greater efficiency and transparency. Yet the subprime loans and sneaky fees that proliferated before the 2008 economic meltdown had precisely the opposite effect. If the fate of the modern financial firm depends on its ability to enmesh consumers in transactions that ill serve their interests, those consumers are in danger — but so is Wall Street and the economy as a whole.

Warren’s detractors cite her lack of experience overseeing a large, complex organization, and that gap in her resume underscores the importance of choosing an able management team. But in the top job, the new agency needs a visionary, not a functionary. Warren would provide a unique voice on Obama’s team of regulators, many of whose other members have deep ties to Wall Street.

Senate Banking Chairman Chris Dodd, a key architect of the financial-reform legislation, suggested this week that getting Warren confirmed might be difficult. But a fight over appointing Warren to lead the consumer-protection agency is a fight worth having.