The Democratic debate format always emphasizes policy. But presidents don’t legislate.

Too many people, as the joke goes, believe in the Green Lantern theory of the presidency — that the commander in chief can conjure into being his or her desired policy outcomes by simply wanting them enough and “fighting” for them. But it’s not really a joke: Many people, including the current occupant of the Oval Office, believe that the president is a CEO who can just order his underlings in the other branches of government around, getting exactly what he wants, legal processes be damned.

But it’s a fundamental distortion that the president is the nation’s bill-writer-in-chief, and that her or his chief function is to be a shepherd for the legislative process. That’s not how it works, and that’s not how it was designed to work. Members of Congress do that — and they have their own priorities, local concerns and scores to settle, all of which affect the direction that bills take, even in our politically polarized times.

Every recent president has campaigned on big legislative efforts that never came to fruition because Congress wasn’t interested. Yet every recent presidential debate has seen the moderators zeroed in on the details of candidates’ legislative proposals, doing voters a disservice.

If earlier debates are any indication, a hefty amount of time during Thursday’s pared-down third Democratic debate will be spent on the details of the candidates’ various legislative plans — particularly health care, which tops the list of policy priorities for Democratic and Democratic-leaning voters in surveys like Pew’s.

Yes, it’s important to know what a candidate believes about the future of America’s health care system. But we only have to go back to 2008 to see that what gets hashed out in a debate doesn’t necessarily mean much once a bill hits the floor in Congress. Back then, Sen. Barack Obama vociferously opposed an individual mandate to buy insurance, and went back and forth with then-Sen. Hillary Clinton about the wisdom of such an idea in debate after debate.

Fast forward to the signing of the Affordable Care Act — now better known as Obamacare — and there the individual mandate was, in all its glory, despite all the sparring during the debates.

And while the moderators and the candidates are focusing on the details of potential legislation that will ultimately be shaped by Congress and not by whomever gets elected, they’ll be ignoring the ways in which a president can vastly change policy all by him or herself.

For instance, in the first two 2020 Democratic debates, though huge chunks of time were spent on health care, the candidates were never asked who they would nominate to be secretary of health and human services — and whether that person would be amenable to granting waivers to states that want to add destructive work requirements to Medicaid, as the Trump administration has done. That’s a real, concrete way in which the executive branch affects health care policy, but you’ll likely never hear a word about it until sometime several months after Inauguration Day, should a Democrat win in 2020.

And the list of areas a president can affect without Congress is long.

For example, foreign policy is another area that famously gets left out of debates, despite the president having tons of latitude to act with impunity. And who the president appoints to head the Federal Reserve and the antitrust division at the Department of Justice has much more bearing on what happens in terms of economic growth and corporate power than does their preferred top tax rate (which can’t be changed without Congress in any case), but you’ll usually hear more about the latter than the former in a debate. The president can’t provide a pathway to citizenship for immigrants without legislative action, but it can reverse rules the Trump administration has put in place that are putting the children of immigrants at risk.

By overseeing the various Cabinet level departments and choosing who leads them, a president has vast powers for which no legislation is required — as Trump is actively discovering. Just consider the folks who could lose access to food stamps, or whose kids could lose access to school lunches, or who will see their children not receive automatic citizenship, or who will not be able to receive much-deserved overtime pay because of administration actions taken by Trump appointees through the rule-making processes without an up or down vote in Congress.

Those aren’t the sort of things that debate moderators ever ask about; they weren’t the subject of a single day of campaign news in 2016.

Perhaps it’s safe to assume that any Democratic administration would undo those rules. But presidents also only have a finite amount of time and focus. They can’t get to everything. So knowing which rules they’d toss out first would be useful to voters by helping them to distinguish between the priorities of different candidates.

And voters who aren’t plugged in to every twist and turn of the administration may learn about these issues for the first time via a debate question. That’s worth something.

So if I had one request for the moderators on Thursday, and in the debates to come, it’s this: Think less about bills, and more about regulations, personnel, power and what the president can do without asking 435 members of Congress to go along with it. Goodness knows Trump has.