Representative Alexandria Ocasio-Cortez is precisely the sort of campaign surrogate you want, especially if you are Bernie Sanders: She is young, energetic, charismatic, popular (with the people she needs to be popular with, anyway), and, happily, currently ineligible to run for the presidency herself.Representative Alexandria Ocasio-Cortez is precisely the sort of campaign surrogate you don’t want, especially if you are Bernie Sanders: She is callow, flippant, vain, shallow, and prone to making policy pronouncements that are even battier than your own, and she forgets to mention you at all in the course of making appearances that are in theory on your behalf.Senator Sanders is, in his bizarre way, the conservative in the Democratic presidential primary: Republicans are accused of “wanting to turn the clock back” to the 1950s, but Sanders, the confessing socialist, wants to turn the clock back to the 1930s. (The senator himself is culturally a product of the 1970s, which is what his weird little rape-fantasy literary œuvre is all about.) In the New York Times, former economist Paul Krugman poo-poos the idea that Senator Sanders means that he is a socialist when he says he is a socialist, but Sanders’s prescriptions do have a certain dustily familiar aspect to them: Health care? Nationalize it by making Medicare an effective public monopoly. Banking? Nationalize it by having the government operate its own banks, i.e. by having the state literally own the means of production.This is not new stuff for the gentleman from Vermont from Brooklyn. He ran for governor of Vermont on a program that included, as those naughty ring-wing radicals over at CNN put it, “nationalization of the energy industry, public ownership of banks, telephone, electric, and drug companies and of the major means of production such as factories and capital, as well as other proposals such as a 100 percent income tax on the highest income earners in America.” Then, as now, he talked like a dorm-room radical, speaking of his desire to “create a situation in which the ordinary working people take what rightfully belongs to them.” The usual socialist prattle: “If workers do not take power in a reasonably short time this country will not have a future.” He now says he no longer supports nationalization of industries, but that is really not quite true: Along with health care and banking, he proposes to effectively nationalize the energy industry (through a so-called Green New Deal) and much else. Like Senator Elizabeth Warren, he favors changes in corporate governance that would allow government to proceed as though it owned the country’s largest firms even if they remained technically private. The point, according to the Sanders campaign, is to “shift the wealth of the economy back into the hands of the workers” because “corporate greed is destroying the social and economic fabric of our society and rapidly moving our nation into an oligarchy.”Senator Sanders is a politically and intellectually unserious man — which is nothing new to American presidential politics, of course. But he has been a radical left-wing Froot Loop long enough to know that there are practical limits to public Froot-Loopery. Representative Alexandria Ocasio-Cortez has not been around long enough to appreciate that fact. Which is why, among Democrats who believe that American law-enforcement agencies are Enemies of the People and that our immigration and border-patrol authorities should be liquidated in order to facilitate the uncontrolled flow of people across open borders, she actually says that American law-enforcement agencies are Enemies of the People and that our immigration and border-patrol authorities should be liquidated in order to facilitate the uncontrolled flow of people across open borders.Senator Sanders knows better than to say that. He also knows better than to believe it. In the long-ago days of . . . 2016, Senator Sanders riled up the gentlemen in Iowa’s union halls giving frankly nationalist anti-immigration speeches that could have been delivered by Donald Trump. “Open borders,” he insisted, were a billionaires’ scheme, a “Koch brothers proposal” to flood the United States with cheap Latin American labor and thereby undermine the power of the workers and their efforts to “take power.” Somebody has given him the intersectionality talk since then, and he no longer sounds quite so much like Pat Buchanan when he talks about immigration.But Representative Ocasio-Cortez is one step beyond, dismaying the Sanders campaign by using her campaign appearances to, among other things, encourage law-breaking by and for illegal immigrants: “Organizing is about tipping people off if you start to see that ICE and CBP are in communities to try and keep people safe,” she says. Organizing to keep law-enforcement agencies from enforcing the law in order to abet illegal behavior isn’t politics — it is criminal conspiracy. Senator Sanders may not care much about that, but he does not want to spend 2020 explaining it away, either.That is because Senator Sanders’s appeal is a nationalist appeal, and the senator himself is, at heart, a nationalist, as indeed were the Democratic giants of American progressivism who preceded him spiritually: Franklin Roosevelt, above all, but also Woodrow Wilson. Representative Ocasio-Cortez is an anti-nationalist, one whose sensibility (it would be too much to describe her posturing as “ideas”) is more oriented toward trans-national class solidarity. Which is to say, her socialism is more of the international variety, whereas Sanders’s socialism is more of the nationalist variety, one that is in tune with familiar Democratic appeals to “economic patriotism” and denunciations of “economic traitors,” which is what Democrats called Mitt Romney when he ran for president in 2012. As my friend Jonah Goldberg argues, on economic questions, “nationalism” and “socialism” end up meaning the same thing: An industry that is nationalized is one that is socialized, and one that is socialized is one that is nationalized.(Somebody really should think up a handy abbreviation for the combination of nationalism and socialism that characterizes our bipartisan consensus today.)Senator Sanders’s camp may not like the way Representative Ocasio-Cortez talks about illegal immigration, but the fact is that the senator has moved her way on the issue rather than moving the Democratic Party his. “Breaking up ICE and CBP” is right there in his campaign literature . . . followed by the words “and redistributing their functions to their proper authorities.” Not exactly open borders. Senator Sanders makes the usual noises about the evils of for-profit detention centers, but he despises for-profit activity at scale categorically. So, what to do? “Convene a hemispheric summit with the leaders of Latin American countries who are experiencing migration crises and develop actionable steps to stabilize the region,” says the Sanders campaign. Actionable steps? Oh!Compare Senator Sanders’s actionable steps to Representative Ocasio-Cortez’s stop snitchin’ and you have a pretty good indicator of the range of Democratic politics today. Poor old Joe Biden must be wondering what the heck happened. (But he has been doing that for a decade or two.) The question for 2020 is whether the path of least resistance leads Biden-style Democrats to Ocasio-Cortez’s ascendant movement or to Donald Trump’s — or to a purgatorial apathy, which Republicans would not reject as a consolation prize.