As Democratic primary contenders race to distinguish themselves from each other, the many senators in the field are introducing a flurry of bills and occasionally co-sponsoring (and occasionally not) each others’ bills. These debates over the various flavors of anti-poverty plans, varieties of Medicare-for-all legislation, and who is and isn’t on board with the Green New Deal resolution are interesting windows into individual politicians’ thinking that collectively reveal a great deal about the broad currents in Democratic Party policy thinking.

They don’t, however, actually tell us very much about how policymaking is likely to vary, whether we’re talking about an Elizabeth Warren administration, a Kamala Harris administration, or an Amy Klobuchar administration.

That’s because any Democratic president is going to have to deal with the same United States Congress — a Congress in which House Blue Dogs and a clutch of red state senators (Joe Manchin (WV), Doug Jones (AL), John Tester (MT), Kyrsten Sinema (AZ), etc.) will limit what bills can pass. The Senate filibuster, meanwhile, will require Republican votes on most legislation, even if Democrats take control. In sum, none of this stuff is going to pass anyway.

That’s not to say the primary doesn’t matter. It’s just that “what legislation will you support” probably isn’t where the differences among Democrats are going to be relevant. There are, instead, five particular areas where the differences will be significant — foreign policy, presidential appointments, legislative agenda-setting, macroeconomic management, and regulatory envelop-pushing.

So far we don’t know too much about what those differences are. Candidates like to talk about their broad vision for the country and reporters tend to cover what’s happening in front of them. Over the next year, we should — as journalists and civic participants— try to press the candidates to explain where they stand on these matters, even as it seems less sexy than fantasizing about what bills they’ll sign.

Foreign policy — where presidents matter most

No president is totally unconstrained in national security matters. Donald Trump has struggled to get the military to execute his desire for a withdrawal from Syria. Barack Obama got rolled by the top brass into escalating the war in Afghanistan. But the formal legal constraints on presidential power are low in the security domain: A president who wants a hawkish approach to Iran, North Korea, Venezuela, or China will be able to get one, but a president inclined to go in the opposite direction could get that done, too.

The parties are not organized around national security issues, so there is a wide range of plausible courses candidates from either party could pursue.

Last but by no means least, to some extent in foreign policy just saying things is a form of policymaking. It matters whether the president refers to Saudi Arabia as a valuable ally or a brutal dictatorship, whether the president mentions the rights and interests of people living in the West Bank or Xinjiang, and whether the president talks about NATO as a valuable American asset or a costly burden.

None of the declared candidates for 2020 have had much to say about international affairs. (Sen. Warren (D-MA) has said the most of the formally announced candidates, but she focused largely on trade issues.) An ongoing controversial war sometimes makes foreign policy a top-tier electoral issue, but that seems unlikely to be the case in 2020. But the centrality of foreign affairs to the actual job of being president means it’s crucial to pay close attention to what they do say and do on the topic.

Presidential appointments: continuity or change

The executive branch is a place where presidents can really shape policy without Congress.

Obama appointed a team that was overwhelmingly composed of center-left technocrats, with few progressive bomb-throwers and a healthy smattering of individuals with considerable ties to the business world. This resulted, particularly in his first term, on an approach to the banking crisis and related issues that was heavily invested in restoring economic confidence rather than pursuing justice (or some would say vengeance) through either the regulatory apparatus or the federal prosecutors.

Someone like former Attorney General Eric Holder was fairly typical in Obama’s administration: He served at a high level under President Bill Clinton before working eight years at the white-shoe law firm Covington & Burling (where he represented the NFL, Merck, Chiquita, UBS, etc.), then ascended to a Cabinet job that he eventually left in favor of a return to Covington. Also not unusual: Holder, from his Covington perch, remains an important player in the party establishment — chairing the party’s effort to fight Republican gerrymanders and otherwise very much in the mix.

Most likely, the next Democratic president will represent continuity with Obama on the level of personnel, whatever her campaign white papers say — just as Obama’s administration represented continuity with Bill Clinton’s despite the bitter 2008 primary with Hillary Clinton. A lot of people who served in the Obama administration will likely serve in the next Democratic administration, many of them after having dallied in the private sector during Trump’s time in office, and many of those who reach the heights of office will eventually depart for gigs in the more progressive corners of corporate America.

But this is not set in stone. Warren, who’s often said that “personnel is policy” and who occasionally picked bitter fights with Obama about relatively obscure appointments, seems very likely to bring in a somewhat different cast of characters. Much of the tension between Sen. Bernie Sanders (I-VT) and the Democratic establishment in DC, similarly, seems driven by a not-fully-articulated fear that he will attempt to staff the government with the Middlebury College faculty rather than the “appropriate” group of ex-Obamanauts and friends. There are questions, in other words, both about the ideological tenor of likely Sanders appointments but also his ability to build a technically competent team.

Sanders, however, has not spoken explicitly about appointments, and the presumption that the rest of the field would offer continuity is, similarly, just a presumption. Obviously candidates for office aren’t going to commit to specific names for Cabinet and sub-Cabinet jobs, but the broad approach to appointments is important.

Trump-era policymaking, for example, has turned out to be far more generically conservative than listening to his pronouncements would have led you to believe. That’s because his administration has been staffed with pretty generic conservative movement figures who could plausibly have served any GOP president.

Priorities matter

As a candidate, Trump promised an ambitious plan to overhaul American infrastructure.

His administration did in fact come up with a version of such a plan, but as a policy priority it took a backseat to efforts to repeal the Affordable Care Act, a giant corporate tax cut, and now a prolonged congressional fight about a border wall.

Similarly, Obama supported a comprehensive immigration reform approach throughout his first term in office. Nut what he actually pursued legislatively was a stimulus bill, the ACA, and the Dodd-Frank financial regulation bill, followed by a failed effort to negotiate a Senate deal around cap and trade. Only when he was reelected did he turn to immigration.

Those immigration discussions produced a bipartisan bill that passed the Senate 68-32 and by all accounts had majority support in the House. But by this time, Republicans held the House majority, and even though most members of Congress supported the deal, most congressional Republicans did not. Consequently, then-House Speaker John Boehner didn’t allow it to come up for a vote.

There’s no guarantee that Obama could have gotten a bipartisan agreement back in his first two years when Democrats held the House. But it’s at least possible that if Obama had focused on immigration rather than financial regulation or health care that an immigration bill would have passed.

By the same token, there’s a big difference between agreeing that a single-payer health care system is a good idea (I think so) and thinking that it would be a good idea for a new Democratic Party administration to spend 2021 on a bruising legislative battle over a single-payer health care bill (I’m skeptical). Politicians will inevitably try to wriggle out of admitting that there are any tradeoffs or limits to what they can achieve, but if asked squarely which of their various initiatives they intended to press for first, they might let us know.

It’s the economy, stupid

The shadow of the Great Recession hangs heavily over any evaluation of Barack Obama’s presidency. But even though the economic crisis he inherited and the painfully slow recovery from it that he presided over very much defined his presidency, it only really became a first-tier political issue in the final two months of the 2008 general election.

The housing slump and ensuing spike in foreclosures came up to an extent during his primary campaign against Hillary Clinton, but the larger question of how to tackle a systemic economic crisis — and how to regulate Wall Street in order to make sure it didn’t happen again — weren’t high on the agenda because the crisis hadn’t happened yet.

Macroeconomic management is an area where presidents do face significant constraints from Congress, but also have a fair amount of discretion. Had Trump wished to appoint a more inflation-averse Federal Reserve chair he could have done so, and both the labor market and his poll numbers would be worse for. Conversely, Obama could have been more aggressive about installing pro-growth Fed appointees and didn’t need to make the premature rhetorical “pivot” to deficit reduction starting in the winter of 2009-’10.

With the Recession not yet that far back in the rearview mirror, asking presidential aspirants what they thought of the recovery and how it could have been made more rapid could be extremely revealing.

Overall philosophy on monetary policy, fiscal stimulus, and how to think about whether or not the United States is currently close to full employment are crucial differentiators. That’s because most politicians don’t have strong views on these subjects and are likely to bring congressional allies along with them whichever way they tack. Yet in a practical sense, the day-to-day performance of the economy is a key determinant of presidential popularity and a key driver of human welfare.

The executive action envelope

Early in his administration, Obama frequently suggested to immigration activists that he lacked the authority to shield unauthorized residents of the country from deportation — no matter how sympathetic their cause might be. Bipartisan legislation and only bipartisan legislation could help them.

By late 2014, however, he’d changed his mind and decided to roll out a sweeping series of executive actions designed to give millions of long-settled people work permits and conditional protection from deportation. He was, of course, challenged in the courts on this, and the legal question has yet to be fully decided.

But what’s beyond question is that Obama was challenging the norms around the purpose of deferred action grants and the circumstances in which they could be made. Trump would go on to seriously violate a wide range of norms around the institutional independence of the FBI and the Department of Justice while installing new leadership at the Consumer Financial Protection Bureau that set about to do basically everything in its power to undermine the agency’s core purpose.

It’s easy to agree that this kind of see-saw of executive action is not ideally how we’d like to policy made. And yet in the real world, a great deal of policy does in fact happen through these channels and members of the same political party can realistically differ a great deal in how far they will push the envelop and in which areas.

Sanders and Senate Minority Leader Chuck Schumer, for example, recently came together to push for legislation that would curb stock buybacks. It’s a good message bill, but this is obviously dead-on-arrival in a filibuster-ridden Senate. And aggressive Securities and Exchange Commission action could, however, try to get something like this done through the rule-making process. How far the next president wants to push the envelope on executive action — and how committed she is to appointing judges who’ll give the green light to aggressive use of the regulatory state — is going to be a key differentiator.

Politics for the real world

Listening to politicians’ broad aspirational visions is an important way to get a sense of how they think and what they value.

But it’s also true that the nature of a primary competition in a crowded field is that the candidates have maximum incentives to draw distinctions between each other, even though real world legislation is a team sport. For President Warren to sign a bill, Sens. Cory Booker (D-NJ), Kamala Harris (D-CA), Kirsten Gillibrand (D-NY), and Sanders are all going to have to vote for it first. So in practice, the outer limits of the policy debate aren’t going to be what constrains outcomes.

Since all possible presidents will be constrained in similar ways by the legislative process, it’s worth paying attention to the more banal real world ways in which presidential leadership matters. Presidents are afforded considerable discretion in building their team, and no White House is so centralized as to make this irrelevant.

In a practical sense, personnel is policy, and that’s especially true when it comes to the question of how aggressively to use regulatory authority, how to manage the macroeconomic situation, and how to run America’s sprawling national security state. Separately but crucially, precisely because no actual president is going to check off her entire policy wishlist, it matters a great deal what in particular the officeholder decides to make a big push for.

This isn’t the kind of stuff that candidates are inclined to talk about, largely because they think voters aren’t interested in it. But to the extent that you’re really interested in the stakes in the 2020 primary, this is the most important stuff to focus on. And if candidates get questions about it — questions from real voters rather than annoying journalists — they’ll have to come up with something to say.

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