Nothing like a president-elect widely feared as an erratic bully to trigger newfound respect on the left for the rule of law, right?

Well, maybe not.

The Harvard Crimson reports that the dean of Harvard College, Rakesh Khurana,

“will prioritize protecting Harvard’s undocumented undergraduates” following the election. A petition demanding that Harvard “create an office specifically meant to cater to undocumented student needs” has “garnered more than 4,000 signatures, and has received endorsements from at least three academic departments,” the Crimson reports.

When it comes to immigration law and enforcement, I’m about the most liberal person one can imagine, but that report made even me chuckle. Imagine if Harvard reacted to, say, federal regulations having to do with sex discrimination as defined in Title IX of the Education Amendments of 1972 with similar brazen and cavalier defiance.

There’s plenty of hypocrisy on all sides. Conservatives who favored expansive executive power back in the Reagan administration — when it looked like Tip O’Neill and the Democrats would control the House of Representatives forever — are of a sudden rediscovering respect for congressional prerogatives now that it’s President Obama facing off against Speaker Paul Ryan in the and Majority Leader McConnell in the Senate. Democrats who railed against President George W. Bush’s warrantless wiretapping and other executive actions are nonetheless happy to defend President Obama’s unilateral actions on immigration and labor law.

As Yuval Levin and Ramesh Ponnuru wrote in National Review back in September, in a piece that merits rereading post-election, “contemporary liberalism has come to ardently champion executive unilateralism…This enthusiasm has waxed and waned, and it is always stronger when Democrats are in the White House.”

The George Mason University law professor and Washington Post blogger David Bernstein covers similar ground, at book length, in his 2015 work Lawless, published by Encounter, with a foreword by Senator Cruz.

In other words, if you don’t have a great deal of confidence in Donald Trump’s character, you might want to consider the merits of the constitutional schema, in which the president doesn’t actually have a whole lot of authority to set policy on his own, but rather is supposed, simply, to execute, faithfully, the laws enacted by Congress.

The principle applies regardless of which party holds the White House. If the president were less powerful to do whatever he wanted to do regardless of Congress, it would merit less of a national freak-out each time the country happened to elect a president that half the country intensely disliked.

The paradox is that the same laws that are so necessary to constrain a potentially bad president are precisely the laws that the Harvard students are eager to ignore when it comes to immigration.

If it’s a paradox, though, it is one with extensive precedent. America, after all, has a long and honorable tradition of civil disobedience, from Samuel Adams’ Boston Tea Party through Harriet Tubman’s Underground Railroad — a flouting of the Fugitive Slave Act — and Rosa Parks’ refusal to go to the back of the bus.

If individual citizens, institutions like Harvard, or state and local governments are going to start taking it upon themselves to disobey or disregard laws passed by Congress, what’s to prevent the president from taking the same provisional approach? As recently as earlier this year, some prominent mainstream thinkers were recommending essentially that path. In his book The Fix, the managing editor of Foreign Affairs, Jonathan Tepperman, writes, “Midway through Obama’s second term, the president got fed up with years of congressional obstruction and announced he’d start going around the House and Senate whenever he deemed it necessary. Using his executive authority, Obama has since moved unilaterally…”

Mr. Tepperman lists a string of examples — halting deportations, releasing “nonviolent” drug offenders, forcing reductions in carbon emissions, requiring federal contractors not to discriminate against gays. One trouble with such actions, especially if undertaken without popular support, is that they are subject to being undone by the next president, who may have different views about immigration, pollution, incarceration, or nondiscrimination.

Another trouble is that if the source for the legitimacy or authority of individual, institutional, or executive action isn’t a law, what is it? President Kennedy, in his inaugural address, reached back to the Declaration of Independence’s “unalienable rights,” declaring, “the rights of man come not from the generosity of the state but from the hand of God.”

Whatever one’s view of the imperial presidency, the rule of law, or how Harvard treats its illegal immigrant students, give even the most cursory consideration to our Founding Fathers, and it’s hard to avoid coming away with respect for the clarity with which they both understood the creator and crafted the Constitution. If Dean Khurana is looking for something to prioritize after the election, those would be points on which to start.

Mr. Stoll is editor of FutureOfCapitalism.com.