Now that Wall Street has been welcomed back to Washington, it should use its return to the corridors of power to repair its tarnished reputation and to restore public confidence in the markets. That’s the least Wall Street can do after exacerbating one of the worst financial crises in history and then carrying on as if nothing bad had transpired. Mr. Trump can help make this happen, but only if he trades the repeal of Dodd-Frank for a wholesale reform of how bankers, traders and executives are compensated on Wall Street. A new system that rewards prudent risk-taking and holds people personally and financially accountable for their actions is a prerequisite to restoring our faith in Wall Street.

It’s been a rough eight years in exile for the big banks. Barely three months into the job, President Obama told the chief executives of the nation’s most powerful banks that his administration was the only thing standing “between you and the pitchforks.” Later he said he did not get elected to help out “a bunch of fat-cat bankers.” There were well-deserved public floggings of bankers in Congress and in front of the Financial Crisis Inquiry Commission. And in July 2010, President Obama signed the Dodd-Frank law, a complex set of rules governing what bankers and traders could do to make money and the risks they could take, intended to prevent another financial crisis.

Dodd-Frank and other financial regulations adopted around the same time have made it much harder for Wall Street to do what it does best: provide much-needed capital to businesses that want it. They are often cited, correctly, as a big culprit behind what Lawrence Summers, the Harvard economist and former Treasury secretary, refers to as “secular stagnation,” an economy that is “stuck in neutral” and condemned to a mere 2 percent annual gross domestic product growth rate.

Meanwhile, Mr. Obama’s Justice Department forced the big firms — or more accurately their shareholders — to cough up more than $200 billion in fines as punishment for, among other things, the role the banks played in knowingly packaging shoddy mortgages into securities and then passing them off as AAA-rated investments. We were led to believe these exorbitant fines were the same as justice, but that’s not remotely true, especially since many of the facts about what happened were whitewashed as part of the settlements and no individual Wall Street bankers, traders or executives have been held responsible for their wrongdoing.

No surprise, Wall Street also became a convenient whipping boy for ambitious politicians like Senators Elizabeth Warren and Bernie Sanders. Their popularity increased exponentially as they fingered Wall Street. Even Hillary Clinton (to keep Mr. Sanders and Ms. Warren at bay) and Mr. Trump (to burnish what seemed to be his populist credentials) got in on the act. As a result, most people don’t know what to make of Wall Street anymore. The combination of silly regulation and relentless demagogy took its toll. The pendulum against Wall Street had swung too far.