A supremely important presidential issue is being generally neglected because Democrats have nothing interesting to say about it and Republicans differ among themselves about it. Four Supreme Court justices are into the fourth quarters of their potential centuries — Stephen Breyer (77), Antonin Scalia (79), Anthony Kennedy (79), and Ruth Bader Ginsburg (82). So, presidential candidates should explain the criteria by which they would select judicial nominees.

Regarding jurisprudence, Democrats are merely result-oriented, interested in guaranteeing three outcomes: Expanding government’s power to prevent protection of unborn babies, expanding government’s power to regulate speech about the government (“campaign finance reform”) and expanding government’s power to discriminate for the benefit of certain government-preferred groups (“race-based remedies”).

Republicans cannot speak their minds about the judicial supervision of democracy because their minds are unsettled. Fortunately, they are being urged, by thinkers like Randy Barnett, to adopt a vocabulary that is disconcerting to conservatives who have grown lazily comfortable with rhetorical boilerplate in praise of “judicial restraint.”

Barnett, a professor at Georgetown’s law school, recently took to a place that needs it — the University of California, Berkeley — this message: “The judicial passivism of the Supreme Court has combined with the activism of both congresses and presidents to produce a behemoth federal government, which seemingly renders the actual Constitution a mere relic, rather than the governing document it purports to be.”

In his lecture “Is the Constitution Libertarian?” Barnett acknowledged that in many respects American life “feels freer” than ever, and that we have more choices about living as we wish. In many other ways, however, the sphere of freedom is too constricted, and individual rights are too brittle, because for decades America’s Lockeans have been losing ground to Hobbesians: “The Lockeans are those for whom individual liberty is their first principle of social ordering, while the Hobbesians are those who give the highest priority to government power to provide social order and to pursue social ends.”

Not all Hobbesians are progressives, but all progressives are Hobbesians in that they say America is dedicated to a process — majoritarian decision-making that legitimates the government power it endorses. Not all Lockeans are libertarians, but all libertarians are Lockeans who say America is dedicated to a condition — liberty. It is, as Lincoln said, dedicated to the proposition that all persons are equal in possession of natural rights.

Lockeans favor rigorous judicial protection of certain individual rights — especially private property and freedom of contract — that define and protect the zone of sovereignty within which people are free to act as they please. Hobbesians say the American principle is the right of the majority to have its way. Last year, 54 Democratic senators (including two so-called “Independents”), Hobbesians all, voted to amend the First Amendment (“Congress shall make no law … abridging the freedom of speech”) to empower majoritarian government to regulate the quantity, content and timing of political speech.

Lockeans say the Constitution, properly construed and enforced by the judiciary, circumscribes the majoritarian principle by protecting all rights that are crucial to individual sovereignty. Lockeans say the Constitution codifies the Declaration of Independence, which, in its most neglected word, says governments are instituted to “secure” natural rights.

Government, says Barnett, serves liberty when its regulations “coordinate individual conduct as do, for example, traffic regulations mandating driving on one side of the street or the other.” Lockeans say that our natural rights, only some of which are enumerated in the Constitution (The Ninth Amendment: “The enumeration in the Constitution, of certain rights, shall not be construed to deny or disparage others retained by the people”), place on government the heavy burden of justifying restrictions of these rights. And, Barnett argues, a nonpassive, properly engaged judiciary bears the burden of saying when the government has not justified its restrictions as necessary and proper.

So, Barnett says, yes, the Constitution — “the law that governs those who govern us” — is libertarian. And a Lockean president would nominate justices who would capaciously define and vigorously defend, against abuses by majoritarian government, what the 14th Amendment calls Americans’ “privileges or immunities.”

Today, Democrats’ intraparty arguments are dull as ditchwater because they concern nothing fundamental, only how rapidly and broadly to expand Hobbesian government’s redistributive and regulatory reach. Republican presidential aspirants must be forced to join their party’s intramural argument about the judiciary’s proper function. Then we can distinguish the Lockean constitutionalists from the merely rhetorical conservatives whose reflexive praise of “judicial restraint” serves the progressives’ Hobbesian project of building an ever-larger Leviathan.

© 2015, Washington Post Writers Group