Leading in to the Michigan primary, Hillary Clinton rolled out a novel attack against Vermont Sen. Bernie Sanders. He "was against the auto bailout," she said at the March 6 debate in Flint, Michigan. Later, and more precisely, she said he "voted against the money that ended up saving the auto industry."

It didn't help Clinton carry the state, but as the campaign moves on to Ohio and other states with auto-related jobs the Clinton campaign says it will keep pressing the attack.

Mook says Clinton will continue to make contrast w/Sanders on auto bailout. "We'll continue to talk about it." — Ken Thomas (@KThomasDC) March 9, 2016

The argument turns on the interpretation of a somewhat obscure sequence of votes. Clinton seems to imply that Sanders was philosophically opposed the idea of assisting the auto industry — but that's wrong. It's more defensible to say that the votes reveal something important about Sanders's approach to the legislative process but that's less obviously resonant with Rust Belt voters.

The argument also touches on a much more profound question that Clinton hesitates to raise. She favored bailing out not just auto companies but Wall Street banks. And she did so not as a legislative tactic, but out of a sincere belief — shared by both Barack Obama and George W. Bush — that failing to do so would bring about economic catastrophe.

Sanders opposed TARP, favored a failed auto bailout bill

Perhaps the clearest account of the votes that are in dispute comes from Keith Hennessey, who ran the National Economic Council for George W. Bush at the time.

As he writes, there were three different relevant votes:

On October 1, 2008, Senator Clinton voted for TARP while Senator Sanders voted against it. TARP became law. On December 11, 2008, Senators Clinton and Sanders both voted for cloture on the motion to proceed to a bill to provide loans to the auto industry, a Senate attempt to marry up legislation with a bill passed by the House the previous day. That cloture vote failed and the bill died. On January 15, 2009, Senator Clinton voted against a resolution of disapproval to release the second $350 B of TARP funds while Senator Sanders voted for this resolution. The vote failed and the resolution died, thus allowing the full TARP funding to be used by President Obama and his team when they took over. This is the vote she highlighted last night.

There are two important things to note here. One is that when specifically voting on a bailout of the auto industry, Clinton and Sanders agreed. The other is that the bill in question didn't pass. The auto industry got bailed out anyway thanks to a discretionary use of TARP funds by the Bush administration, which made a relatively small loan that essentially kept the industry on life support until Obama could take over and make a real policy. Then a subsequent second discretionary use of TARP funds was used by the Obama administration, which provided larger sums of money and temporarily nationalized Chrysler and General Motors as part of a larger restructuring initiative.

The Sanders campaign's view is that when Sanders had a chance to vote on the auto bailout question, he voted in favor of doing an auto bailout. And he certainly didn't object to Bush or Obama using TARP funds to do the auto bailout.

The Clinton campaign is hanging its hat on that third vote. By this time, Sanders's preferred route to an auto bailout had already been foreclosed. TARP funds, instead, were being used for that purpose. Clinton voted in favor of releasing the second half of TARP, which allowed the auto bailout to go forward. Sanders voted against releasing the money, objecting to its main Wall Street function rather than to its secondary auto function. But without the money, the auto bailout that actually happened couldn't have happened.

Key validators agree with Sanders

This is the kind of situation where elite establishment opposition to Sanders could have been deadly. If everybody who's anybody jumped up and agreed with Clinton's characterization of events, it would do real damage to Sanders's campaign, which is presumably why Clinton brought it up. But actual events went in the other direction.

"Secretary Clinton’s attack misleads Michigan voters and others who supported the auto loans," wrote Hennessey, "She is playing semantic games in an attempt to create a policy difference where none exists."

On CNN, David Axelrod, chief strategist for Obama's campaigns, called the attack on Sanders "too cute by half" and a "cheap shot."

Two ways of interpreting the dispute

One way of interpreting this dispute — certainly the main way Clinton put it in the debate — is as primarily about philosophy. Did Sanders oppose bailing out the auto industry? The answer here seems pretty clearly to be that he did not. When given the opportunity to vote on a standalone auto bailout, he voted yes. And when given the opportunity to articulate his objections to TARP, sending money to the auto industry wasn't on the radar.

Another interpretation is as a dispute about Sanders's approach to legislating.

Here, a legislator like Sen. Debbie Stabenow of Michigan is an instructive example.*

Like Sanders, she voted against creating TARP in October.

Like Sanders, she voted in favor of the failed auto bailout in December.

Unlike Sanders, she voted to release the second round of TARP funds in January.

Stabenow and Sanders, in other words, had the exact same views on the underlying issues — Wall Street bailout bad, auto bailout good — but their TARP II votes differed because they put different relative weight on these issues. To Stabenow, helping out Michigan was more important than refusing to help out Wall Street. To Sanders, it was just the reverse.

This is somewhat similar to the Clinton-Sanders disagreement over the 2007 immigration bill.

The provisions of that bill most important to Democratic primary voters were the ones creating a path to citizenship for people working and living in the United States illegally. Sanders favored those provisions, but he voted against the bill because he objected to business-friendly guest worker provisions that it also included.

In both cases, Sanders thought it was more important to take a stand against malign pro-business initiatives than to deliver concrete progressive wins they were attached to.

The TARP disagreement is much more important

Of course, Sanders isn't running against Debbie Stabenow. He's running against Hillary Clinton. And while Stabenow may have voted for TARP II out of concern for the auto industry, Clinton voted in favor of TARP for the same reason the Bush administration proposed it in the first place: Most economists, and certainly most economic policymakers in Washington, regarded it as necessary to prevent a depression-scale economic collapse.

Unlike the back and forth over the auto industry, this really does reflect a significant conceptual disagreement between Clinton and Sanders — both in terms of their specific view of the financial crisis, and more broadly in terms of who they listen to about difficult questions.

Actually debating this issue in a straightforward way would be a service to the public, but it's risky terrain for both campaigns.

For Clinton, the downside is that, obviously, Wall Street bailouts have never been a great vote getter, and defending them will allow Sanders to reiterate his notion that Clinton and the political establishment are fundamentally corrupt, handing out bailout money to the same bankers they rely on for campaign funds.

For Sanders, the downside is that TARP puts him on the opposite side of Barack Obama, Nancy Pelosi, Harry Reid, Elizabeth Warren, Janet Yellen, and other leading figures in the Democratic Party. The ambiguity Sanders has wrestled with throughout this campaign is that while most Democrats like Sanders and agree with much of his agenda, relatively few of them endorse the sweeping criticism of the Democratic Party's current leadership that is implicit in his political revolution.

Much more so than the auto bailouts, TARP is an excellent example of the two-sided coin that is the 2016 Democratic primary. Sanders's view is almost certainly the more popular one among Democrats, yet it reveals him to have a fairly profound disagreement about the fundamentals of economic policy with an Obama administration that is also very popular with Democrats.

* Correction: An earlier version of this article referred to Stabenow as a former Senator when in reality she has served continuously since 2001.