If you agree with Democrats that Wall Street should be reformed, Hillary Clinton’s more comprehensive solution better grasps the world of finance today. Photograph by Daniel Acker / Bloomberg via Getty

On Monday, in a Times op-ed headlined “How I’d Rein In Wall Street,” Hillary Clinton expressed skepticism that restoring the Glass-Steagall Act, which once separated investment banks from commercial banks, would do much good. It wouldn’t “help contain other parts of the ‘shadow banking’ sector,” she argued. “We need to tackle excessive risk wherever it lurks, not just in the banks.” Though she didn’t mention her main challenger in the Democratic Presidential primary, Clinton seemed to have digressed from her list of proposed reforms, by mentioning one way she would not rein in Wall Street, so that she could get in the last word against Bernie Sanders. Three weeks earlier, in the second Democratic primary debate, Sanders twice mentioned reëstablishing Glass-Steagall, twinning it with a pledge to “break up the big banks.”

Clinton’s beyond-the-banks rhetoric, in the op-ed and in the debate itself, is meant to position her as tougher on the finance industry than Sanders, a move that is hard for her to make convincingly—one has the sense that Sanders would strip every last cufflink off every investment banker, if he could. If you agree with the Democrats that Wall Street should be reformed, though, Clinton’s more comprehensive solution better grasps the world of finance today. Not only are Sanders’s bogeybanks just one part of Wall Street but they are getting less powerful and less problematic by the year. “It ain’t complicated,” Sanders said during the debate. But Clinton is right: it is.

To critics, the Problem with Wall Street can be separated into five distinct problems: the Wall Street rich are strangling democracy with money and clout; Wall Street’s inherent recklessness will imperil the economy again as it did in 2008, especially if its financial institutions are “too big to fail”; Wall Street speculators are a parasite on the real economy; Wall Streeters don’t pay their fair share of taxes; and their super-salaries are a shocking offense against fairness in an era of acute income equality. (I work on Wall Street, in private equity, and while I don’t think that I earn a super-salary, I also know there’s no way to justify how much I make relative to a nurse.)

Sanders would almost certainly agree that these are problems. He’d probably add a few more just to make his point. (In the debate, he said that Wall Street’s “business model is fraud and greed.”) Yet his answers seem to consist of a broad personal solution and a narrow policy solution. The main way that Sanders would counter Wall Street power is Bernie Sanders, in all his lovably crotchety, Wall Street-donation-denying, incorruptible Bernieness. But when Sanders discusses how this would happen in policy terms he demonstrates an obsessive focus on breaking up the six largest U.S. banks and reëstablishing Glass-Steagall. His Web site, too, is a hedgehog where Wall Street is concerned, burrowing deeply into his big idea of a big-bank breakup.

Clinton’s fox-like, forty-eight-hundred-word plan for smaller, wider reforms contains so many details that it’s impossible not to quibble with some of them. But their breadth and diversity capture Wall Street’s diffuseness and variability. In finance, there is a divide between the “sell side,” the banks selling financial advice and services, and the “buy side,” the thousands of asset managers—mainly hedge funds, private-equity funds, venture-capital firms, and mutual funds—that sometimes use the sell side’s services to invest money. And if there is a central story of Wall Street since the nineteen-nineties, it has been the stagnation of the sell side and the rise of the buy side, because of technology, regulation, and new profit opportunities.

In the past decade, electronic-trading platforms that connect buy-side investors to one another have cleared out floors of traders and other sell-side intermediaries, leading to developments like Morgan Stanley’s recent decision to lay off twenty-five per cent of its bond and currency traders. Meanwhile, many of the Dodd-Frank regulations introduced, after the 2008 financial crisis, forced sell-side banks to shift in countless and surprising ways to less-risky business lines, becoming less profitable as a result. Dodd-Frank’s Volcker Rule, which severely limits proprietary trading, in-house hedge funds, and private-equity funds within banks, came for the banks at an inopportune time: during the middle of a golden age of new profit opportunities for hedge-fund and private-equity managers. The low interest rates that have prevailed since 2002 have impelled institutional investors, like pension funds and college endowments, to seek higher returns on huge volumes of capital through those funds, which now collectively manage about $7.4 trillion. All of this has unquestionably hurt the sell side. In 2014, the net income of the six large banks Sanders worries about was sixty-nine billion dollars, seventeen per cent below 2006 levels. If you exclude Wells Fargo, whose income figures are skewed by a merger, the other banks’ income was down thirty-eight per cent.

The shift in power on Wall Street is no secret; it was front-page news, after all, when Marco Rubio received the endorsement, last month, of the hedge-fund manager Paul Singer. But Sanders’s bank-breaking solution doesn’t seem attuned to the changes. Only one of the five problems associated with Wall Street—the risk that the Street’s recklessness will imperil the economy, especially if those risks are concentrated in “too big to fail” institutions—can generally be seen as a sell-side issue. The other four are now mainly related to the buy side: the political spending (Singer alone gave eleven and a half million dollars in the 2014 election cycle, almost six times more than everyone at Morgan Stanley); the seemingly good-for-nothing speculation (at least you can get a checking account at Wells Fargo); the low tax rates (even Jeb Bush has called for higher taxes on “carried interest,” which is primarily an issue for private-equity funds); and the astonishing paydays. When it comes to pay, yes, an investment banker at Goldman Sachs makes mad money, but in 2014, according to Forbes, the top twenty-five hedge-fund managers—individuals, not firms—made twelve and a half billion dollars from profits they earned as asset managers and appreciation in their own managed investments. That is only two hundred million dollars less than the total compensation expenses for every employee at Goldman Sachs. And 2014 was a bad year. In 2013, the top twenty-five managers made more than twenty-four billion dollars.

So why is Sanders so obsessed with Glass-Steagall and the big banks? It seems to be a matter of personal style and historical tradition: as a socialist, Sanders is echoing political ancestors who railed against Big Banks, Big Oil, Big Everything. He also appears to be fighting the last war, of the 2008 financial crisis, out of a conviction that the “too big to fail” banks still pose a systemic risk to the economy. This conviction has some basis in fact: though the big Wall Street banks’ net incomes are declining, the five largest commercial banks did still hold forty-five per cent of the industry’s total assets at the end of 2014. But breaking up the banks, like vetoing the Keystone XL pipeline, seems to be a classic Washington solution: a single political act that can symbolically and almost miraculously address more intractable problems, like income inequality or the consumption of fossil fuels. Neither that nor reëstablishing Glass-Steagall would do anything much to change the bulk of Wall Street. (In her Times piece, Clinton argued that it wouldn’t have done much to prevent the 2008 crisis, either; Megan McArdle concluded the same thing in a detailed post last month for Bloomberg.)