Noah Feldman is a Bloomberg Opinion columnist and host of the podcast “Deep Background.” He is a professor of law at Harvard University and was a clerk to U.S. Supreme Court Justice David Souter. His books include “The Three Lives of James Madison: Genius, Partisan, President.” Read more opinion SHARE THIS ARTICLE Share Tweet Post Email

Photographer: Saul Loeb-Pool/Getty Images Photographer: Saul Loeb-Pool/Getty Images

2015 was supposed to be the year President Barack Obama would use unilateral executive action to accomplish major goals of his administration that had been blocked by Congress: relaxing deportations, closing the prison at Guantanamo Bay, Cuba, and restricting access to guns.

But all three goals stalled. Obama’s executive action on immigration, announced in November 2014, was stymied in the federal courts, and the Supreme Court has yet to decide whether to hear the administration’s appeal. An executive plan to close Guantanamo, rumored to be on the verge of announcement, was held back after the Paris attacks. And although some executive action on guns is still expected in the new year, it’s sure to be challenged in court and, as a result, may not take effect during Obama’s presidency.

For liberals who relished the idea of Obama unbound, the limitations on executive action, both legal and political, feel like unfair usurpations of legitimate presidential power. For conservatives who don’t like the policies that Obama would enact, the delays surely come as evidence that the tripartite system of government is a working relationship.

Who’s right? The question is important -- and not just because it’s a reminder that liberals don’t always favor a weaker executive nor conservatives a stronger one. If the next president is Hillary Clinton, it’s likely to recur, because the Senate seems unlikely to turn Democratic and the House even less so. The season of New Year’s resolutions is a good time to ask yourself: What do you really believe about executive power, independent of who occupies the office?

There are, very roughly speaking, two different ways to think about the constitutional separation of powers. One is essentially textual and historical. It asks what the Constitution says. And because the Constitution's pronouncements on each branch’s power are cryptic and brief, this approach also asks how it’s been interpreted over the years.

The other way of addressing the question is functional. It asks how our government works in practice -- and how we want it to.

Start with the words of the Constitution itself, which give “all legislative powers herein granted” to Congress; “the judicial power” to the judiciary; and “the executive power” to the president.

Advocates of the so-called “unitary executive” like to emphasize that Congress’s powers are limited to those enumerated, while the president’s executive power is unmodified except by the definite article. But it’s possible to make too much of that argument. The framers -- especially James Madison -- thought that, by definition, the job of the executive was to execute the laws made by Congress. The limitations on Congress’s powers were therefore understood as extending to the president as well.

The other powers of the president, such as his roles as commander in chief and treaty maker, were expressly granted by the text of the Constitution -- and they could only be exercised in conjunction with Congress, which retained the power to declare war and (through the Senate) to approve treaties.

The upshot of all this is that the Constitution won’t really tell you what you should think about unilateral executive action. Rather, whatever you conclude can be read backward into the text.

Custom might be a better guide. It’s traditional for the courts to treat the history of executive action as a “gloss” upon the president’s constitutional powers when they’re deciding who’s in charge of what. Seen in historic terms, Obama’s struggles with executive action make a good deal of sense.

Previous presidents have announced policies of de facto amnesty for some categories of otherwise undocumented immigrants. But it’s fair to say that none of these plans went as far as Obama’s, or affected as many people.

Obama did take executive actions on gun control in 2013. But those 23 actions -- including improving the accessibility of federal data for the background check system -- should presumably have gone as far as Obama was empowered to go. Coming up with meaningful new actions that don’t exceed the president’s authority is going to take some serious legal creativity.

As for Guantanamo, there’s room for a creative legal theory that would allow the closure, especially if the administration emphasizes the president’s authority over prisoners of war during wartime. But it’s only fair to acknowledge that, where Congress has expressly spoken -- as it has with regard to transferring Guantanamo detainees to the mainland -- the president’s powers are at what Justice Robert Jackson once called their “lowest ebb.”

Shifting to the functional approach demands that we ask whether it makes sense for the president to be able to break gridlock on highly controversial political issues. Immigration, Guantanamo and guns are all issues on which it possible for reasonable people -- and also unreasonable people -- to disagree. It’s no coincidence that these intensely controversial issues, which split the country on grounds of ideology and culture, would result in blockage of government action.

It can be terribly frustrating and even dysfunctional to live under a constitutional system that invites gridlock in the face of controversy. The U.S. constitutional system does that -- not only by legal design, but also by functional design. Our two-party system over time developed the norm of allowing the party without the presidency to block action, especially when it controls Congress.

Liberals today might not like that. But they should remember that if Donald Trump became president, they’d suddenly become ardent advocates for limitations on what the president could do alone. As for conservatives, the next time they control the presidency, they should remember their own arguments for limiting presidential power -- and not curse the courts or politics when those forces encourage gridlock the next time.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.