None of this is new or controversial information; you can find it in a recent Government Accountability Office report to Congress. What is less well known, however, is that many countries have instituted consumer protections against such hidden taxes, while the United States, which has some of the developed world’s highest interchange fees, has left them completely unregulated.

True, there’s an antitrust class action suit by merchants pending, but its resolution is a long way off and it’s unclear if or how it would benefit consumers. And while several legislative proposals are sitting patiently in Congress, they would at best only chip around the edges of the problem.

Instead, Washington should take two straightforward steps.

First, Congress should recognize the obvious: debit cards, whose use and fees are growing at a rapid rate, are actually no more than plastic checks. Congress and the Federal Reserve do not allow banks to charge their customers a percentage of each check, and it should put the same restriction on debit cards.

Second, Congress should authorize the Federal Reserve to limit credit card interchange fees to their actual cost, fairly determined, plus a reasonable profit. The annual savings to merchants would be in the tens of billions of dollars. Since retailing is highly competitive, most of these savings would be passed on to consumers in lower prices or in the form of improved services by retailers that could afford to hire more people.

How can we be sure this would work? Because other countries have already done it. In Australia, for example, regulation brought the credit card interchange rate down from .95 percent to .50 percent  compared to our approximately 2.0 percent. Five years of experience has confirmed that the payments system works fine; in 2008, the Reserve Bank of Australia estimated the savings during the previous year to have been around 1.1 billion Australian dollars (approximately $1 billion).