I’ve been trying for months to put my finger on what exactly it is about Ted Cruz that I find so frustrating. I think I’ve finally figured it out. Cruz’s rhetoric is stuck in the 1980s, when Ronald Reagan was riding high. You almost get the impression that the exceptionally bright Texas senator hasn’t had a new thought in decades. The only things Cruz says on the stump that would be out of place in that era, when he was in middle school, are his references to repealing Obamacare and defeating ISIS, for which we could easily find early ’80s equivalents.

Cruz has taken Ronald Reagan’s line from his first inaugural address that “government is not the solution to our problem; government is the problem” and made it the basis of his entire campaign. In the Liberty University address last March that kicked off Cruz’s own presidential bid, he ran through a litany of ways he would get government off our backs, mostly by slashing regulations and taxes and defending Second Amendment rights and religious liberties. These are all very important things to do, to be sure. But Reagan’s anti-government message was rooted in the context of his time: Reagan said that “in the present crisis, government is not the solution,” not that government is never the solution. Later on, recognizing that America is not just home to government-loathing libertarians, Reagan added, “it’s not my intention to do away with government,” and that “government can and must provide opportunity, not smother it; foster productivity, not stifle it.”

In short, Reagan believed that government ought to be restrained and limited, but also that it had a vital role to play in improving the lives of Americans. Cruz, in contrast, struggles to do anything other than rail against the federal leviathan. As Yuval Levin, editor of National Affairs, has argued, “he proposes himself as the one who would take us back to a time when the country grasped that conservative ideas could help address our problems.”

These out-of-date talking points are doubly frustrating, because this really ought to be Cruz’s moment. In Thursday night’s Fox News debate, he was masterful. Cruz dismantled Donald Trump for his contradictory stances on immigration, and he made Trump look small by scolding him as one would an insolent child. Of all Trump’s remaining Republican rivals, it is Cruz who has had the most success, having bested the GOP front-runner in five states. Nevertheless, there is a lingering fear in anti-Trump circles that Cruz is too unappealing to be the GOP standard bearer, and that he can’t hang in primaries that aren’t dominated by the hard-right, church-going Christians who are his most devoted supporters. The reason, I suspect, is that he’s just not very modern.

Cruz’s chief rival for the affection of Republican regulars is still Marco Rubio, a man who is roughly the same age as Cruz, yet who seems much younger. Though Rubio is very nearly as orthodox a conservative as Cruz is, his sunnier disposition, his wit, and his emphasis on his lower-middle-class, aspirational roots make him seem more broadly appealing. It’s easy to understand why Cruz’s conservative nostalgia might appeal to older GOP primary voters, who remember the Reagan era as the prime of their lives. But the world has changed a lot since the Gipper left office. The United States is older, more urban, and more diverse. The share of children raised in single-parent families is much higher, and the economic prospects for non-college-educated men are far bleaker. The rich are richer and the poor are in many respects more isolated. Rubio has made an attempt to adapt to this landscape, and to speak to the challenges it raises. His attempt has been imperfect to say the least, but he has at least made an attempt. Cruz hasn’t done the same.

Cruz’s Reaganite prescriptions aren’t entirely irrelevant circa 2016. Overhauling the tax code really could spur investment, and thoughtful deregulation may well lead to more competitive markets and more flourishing startups. But does Cruz really believe that repealing Obamacare will lead to a renaissance for manufacturing employment, as he seemed to suggest on Thursday night? The idea strains credulity.

I am coming around to the view that Cruz is better placed than Rubio to prevent Trump from winning the GOP presidential nomination, and I found it encouraging that Cruz and Rubio spent more time attacking Trump in this latest debate than they did going after each other. Anti-Trump Republicans have been pushing for a Cruz-Rubio alliance, and it looks as though just such an alliance might be coming into shape.

To be at the top of the ticket, however, Cruz must make it clear that he understands America in 2016, and how different it is from America in 1986. He’s made some tentative gestures in this direction, talking up the idea of “opportunity conservatism,” a government-shrinking agenda of school vouchers, expanded gun rights, and labor market deregulation designed to better the lives of the poor. The truth, however, is that this agenda is unlikely to prove all that inspiring to voters outside of Cruz’s very conservative base.

A better tack might be for Cruz to declare himself a believer in a more inclusive, big-tent conservatism. Given Cruz’s deep affection for the Constitution and the principle of federalism, he ought to emphasize that by reining in the federal government, he aims to free state and local governments to pursue their bliss. His mission would not be to impose Texas’ more austere vision of government’s role on California, or California’s more activist vision on Texas, but rather to ensure that both visions can rise or fall on their merits.

The beauty of this approach is that it so clearly aligns with what Cruz actually believes—that a one-size-fits-all government is a poor fit for a sprawling continental republic of 320 million. As an added bonus, running as the candidate of a more robust federalism would send a signal to more socially moderate Republicans that he is willing to let them live in peace. That is just the kind of reassurance that might get big-money donors to open their wallets, and rank-and-file voters to pull the lever for a man who’s working so hard to channel Reagan.