Ross Douthat on the State of the Union By keeping the lowest profile of his presidency, President Obama has enjoyed a relatively successful political season. Since the end of last summer's debt ceiling battle, his approval ratings have gradually ticked up, the economy has improved modestly and his potential rivals for the presidency have bloodied one another in ways that make him look more appealing by comparison. Unfortunately, the president can't run for re-election by staying out of sight. Although if the Republicans actually nominate Newt Gingrich, he might be sorely tempted. Thus the significance of Tuesday night's State of the Union address, which doubled as Obama's re-entrance into the political fray. The address made plain what has been increasingly obvious for some time. After flirting with the role of the reasonable centrist after his party's defeat in 2010, President Obama has decided to run for re-election as a full-throated liberal populist. There were rhetorical nods to deficit reduction, sensible regulatory reform and the Lincolnian idea that "government should do for people only what they cannot do better by themselves, and no more." But the substance of the speech could be summed up in one word: More. More spending on education. More spending on infrastructure. More money for green energy projects. More assistance for homeowners who are underwater on their mortgages. More tax breaks for manufacturers - for high-tech manufacturers, for manufacturers who relocate to poor areas, for manufacturers who retrain workers, for manufacturers who don't outsource jobs, for manufacturers who upgrade their buildings ... O.K., I lost count. And all of it to be paid for, inevitably, by more taxes on the wealthy. Some of this will be popular. Certainly the unifying theme of the address, the idea that public policy should be crafted with the strongest possible emphasis on fairness for a struggling middle class, will resonate with many millions of Americans who have lost jobs or seen wages stagnate across the last five or ten or twenty years. In a campaign against a Republican Party that too often reduces domestic policy to the quest for upper-bracket tax cuts - and a likely Republican nominee who has spent his entire life inside those brackets - it's easy to see why the White House thinks a populist message will be a winning one. But there are perils to the president's approach. One is political: The idea of fairness is popular, but the idea of growth is generally more powerful in American elections, and a message that lays so much emphasis on the need to make sure Warren Buffett is paying the highest possible tax rate risks coming across more anti-rich than pro-prosperity. As William Galston pointed out this week in The New Republic online, polls consistently show that the public is much more concerned about economic opportunity than inequality per se and disinclined to embrace narratives that pit the successful against the poor. In this climate, a populist re-election campaign will have to walk a fine line: As Galston puts it, the president must "address middle class anxieties, but without triggering long-standing middle class fears about redistributive measures that could deepen their plight." The more serious peril, though, has to do with policy rather than politics. A campaign narrative premised on more places this administration on a collision course not just with the Republican Party, but with budgetary arithmetic itself. The Buffett rule will not bring our outlays into line with our revenues. Raising taxes on the richest 1 percent will not cover the projected cost of Medicare and Social Security once the baby boom generation has retired. New spending on energy and education will not pay for itself. And the rhetoric of fairness is not a substitute for a long-term deficit reduction plan, a real blueprint for overhauling the entitlement system, or a comprehensive tax reform - none of which this White House will be offering, apparently, in the 2012 campaign. Instead, Obama proposed general guidelines for reform, but not reform itself. He endorsed the idea of restructuring our public sector without presenting any details for how to do it. He promised a leaner government without specifying where he'd slide the knife. And if he runs on this platform and wins re-election, he'll have won a mandate for doing little or nothing about the challenges that are likely to define his second term.