WHEN I moved to Washington, D.C., in 2002, you could sense that the nation’s capital had turned a corner after decades of decline. But the Washington of 10 years ago still looked basically like the city that had been scarred by riots in the 1960s and then emptied by white flight, with a prosperous northwest divided from a blighted south and east, and frontiers of gentrification that weren’t that many blocks from the Capitol itself.

No doubt there were boomtowns in the 19th-century Wild West that changed faster than D.C. did over the ensuing decade. But the changes to Washington have been staggering to watch. High-rises have leaped up, office buildings have risen, neighborhoods have been transformed. Streets once deserted after dusk are now crowded with restaurants and bars. A luxurious waterfront area is taking shape around the stadium that the playoff-bound Nationals call home. Million-dollar listings abound in neighborhoods that 10 years ago were transitional at best.

And that’s just inside the District proper. Cross the bridges into Virginia or shoot north into Maryland, and you’ll find concentrations of wealth greater than in the richest counties around New York and Los Angeles and San Francisco. Last week, new census data revealed that 7 of the 10 richest American counties in 2011 were in the Washington, D.C., region. Fairfax, Loudoun and Arlington Counties, all in Northern Virginia, have higher median incomes than every other county in the United States.

Whence comes this wealth? Mostly from Washington’s one major industry: the federal government. Not from direct federal employment, which has risen only modestly of late, but from the growing armies of lobbyists and lawyers, contractors and consultants, who make their living advising and influencing and facilitating the public sector’s work.

This growth is a bipartisan affair. It’s been driven by the contracting-out of government services under both Bill Clinton and George W. Bush (as Andrew Ferguson put it in a wonderful Time magazine essay on the new Washington, “government hasn’t shrunk; it’s just changed clothes”); by the Bush-era security buildup, whose ripples are spreading to this day (witness the new Department of Homeland Security facility intended for still-impoverished Anacostia); and by the bright young college graduates who flooded the city at the dawn of Barack Obama’s presidency and the lobbyists who followed to claim a piece of his attempt at a new New Deal.

If you don’t mind congested roads and insanely competitive child rearing, all this growth is good news for those of us inside the Beltway bubble. But is it good for America? After all, like the ruthless Capital in “The Hunger Games,” the wealth of Washington is ultimately extracted from taxpayers more than it is earned. And over the last five years especially, D.C.’s gains have coincided with the country’s losses.

There aren’t tributes from Michigan and New Mexico fighting to the death in Dupont Circle just yet. But it doesn’t seem like a sign of national health that America’s political capital is suddenly richer than our capitals of manufacturing and technology and finance, or that our leaders are more insulated than ever from the trends buffeting the people they’re supposed to serve.
For Mitt Romney and the Republican Party, what’s happened in Washington these last 10 years should be a natural part of the case against Obamanomics. Our gilded District is a case study in how federal spending often finds its way to the well connected rather than the people it’s supposed to help, how every new program spawns an array of influence peddlers, and how easily corporations and government become corrupt allies rather than opponents.

The state of life inside the Beltway also points to the broader story of our spending problem, which has less to do with how much we spend on the poor than how much we lavish on subsidies for highly inefficient economic sectors, from health care to higher education, and on entitlements for people who aren’t supposed to need a safety net — affluent retirees, well-heeled homeowners, agribusiness owners, and so on.

There’s a case that this president’s policies have made these problems worse, sluicing more borrowed dollars into programs that need structural reform, and privileging favored industries and constituencies over the common good.

But this story is one that Romney and his party seem incapable of telling. Instead, many conservatives prefer to refight the welfare battles of the 1990s, and insist that our spending problem is all about an excess of “dependency” among the non-income-tax-paying 47 percent.

In reality, our government isn’t running trillion-dollar deficits because we’re letting the working class get away with not paying its fair share. We’re running those deficits because too many powerful interest groups have a stake in making sure the party doesn’t stop.

When you look around the richest precincts of today’s Washington, you don’t see a city running on paternalism or dependency. You see a city running on exploitation.