There are no two words in politics I hate hearing more than "class warfare."

You'd think I'd like the term. For the last seven years, I've been researching class and politics in America. Class warfare should be my thing. But it's just a huge lie, a metaphor used by elites to cover up the fact that they've already won. The simple fact is you can't have a war when there's only one side. And right now, one class of Americans is almost entirely locked out of our political institutions.

So don't listen to the class war nonsense. Here are five ways that class actually matters in American politics.

1) Our political institutions are packed with rich people

To have a class war in American politics, you need two sides. But those two sides don't exist in America's political institutions.

Here's the not-so-secret truth about America's political system: the people who run it are almost all rich. In January, the Center for Responsive Politics reported that the median net worth of members of Congress has reached a record high of $1,008,767. Millionaires make up just 3 percent of the country, but on Capitol Hill, they're firmly in the majority (and in the Senate, they're a super-majority). And Congress isn't alone: millionaires have a 5-4 majority on the Supreme Court and a man in the White House, too.

People who work in manual labor and service-industry jobs have made up more than half of the country since at least the start of the 20th century — but they've never made up more 2 percent of Congress. Even as other historically underrepresented groups like women and racial or ethnic minorities have (thankfully) started to make up closer to their fair share of our political institutions, working-class Americans have remained sharply underrepresented.

And that's not going to change anytime soon. The makeup of state and local legislatures — which tends to foreshadow demographic changes in national offices — suggest that, if anything, working-class representation may decline even further. In state legislatures, for instance, women's representation skyrocketed from 8 percent to 24 percent between 1976 and 2007, and the share of lawmakers who were black or Latino grew from 9 percent to 11 percent. During the same period, the share of state legislators from blue-collar jobs fell from 5 percent to 3 percent.

You won't hear many candidates or pundits talk about this during campaign season (except perhaps in the rare elections that feature a blue-collar candidate), but one of the most important ways that class matters in American politics is this: our political institutions — the institutions that make the final decisions about the issues that divide rich and poor Americans — are all packed with wealthy, white-collar professionals. And they're likely to stay that way.

2) Yes, the big problems do divide America by class

So why does it matter if political institutions are packed with rich, white-collar workers? Because class actually does divide American politics.

Since pollsters started surveying Americans in the 1930s and 1940s, we've known that people from different economic classes have different views about issues like tax policy, the social safety net, and the minimum wage. And of course they do. Your experience of the economy is a lot different if you're the guy making minimum wage than it is if you're the guy paying his workers minimum wage.

The figure above (from chapter one of my new book White-Collar Government) illustrates just two of the many examples that are out there. In the 1950s and the 1960s, people who did manual labor jobs were vastly more likely to say that they thought the government should guarantee employment and a minimum standard of living. Today, workers are vastly more likely than managers to say that they think the federal government should increase aid to poor people. When it comes to the economy, Americans on the top are a lot less likely to support policies that help Americans at the bottom.

3) Rich politicians tend to support policies that rich people like

What's true for people is, unsurprisingly, true for politicians.

There's an old school of thought that says that it doesn't matter whether rich or poor politicians represent us. Alexander Hamilton once argued that working-class Americans see wealthier people as "their natural patron[s] and friend[s]" and that workers know "that however great the confidence they may justly feel in their own good sense, their interests can be more effectually promoted by the merchant than by themselves."

That's a very convenient opinion, especially for rich people. But Americans from different classes don't always have the same interests or want the same policies. Politicians are no exception.

As with the rest of the population, politicians who spent more time doing working-class jobs are more likely to support progressive economic policies — whether they're Republicans or Democrats, experienced lawmakers or first-term members, members of Congress or members of a city council. Likewise, lawmakers from white-collar jobs — and especially those from high-paying jobs in the private sector — are more likely to support the more conservative policies typically favored by the wealthy.

Here's one example from White-Collar Government. If you look at the scores the AFL-CIO gives members of Congress based on how they vote on major economic bills, legislators who spent more time running businesses and farms tend to be more conservative on economic issues (even when I control for things like party, constituency, campaign donations, etc.), while those who spent more time doing working-class jobs tend to be more liberal on economic issues — just like ordinary Americans.

The same thing is true when you look at any other measure of economic decision-making: how members of Congress are rated by organizations (like the Chamber of Commerce), the kinds of bills they introduce, even what legislators say in confidential surveys about their personal political beliefs.

And it's not just Congress. States where the legislature has more working-class members tend to spend larger percentages of their budgets on social safety net programs. Cities, too.

Other scholars who have analyzed the differences between more and less affluent politicians have reached the same conclusions. Members with more personal wealth are more likely to oppose the estate tax. Members who are more privileged care less about reducing economic inequality. It really matters that we have such a white-collar government.

Does that mean rich politicians are evil, corrupt robber-barons? No. It means that politicians are people, too. Like the rest of us, their views are partly shaped by the experiences they've had, including the kinds of jobs they've had and where they've been in our economic system. As John Boehner is fond of saying about his career as a business owner, "It gave me a perspective on our country that I've carried with me throughout my time in public service." Politicians from different classes aren't fighting a class war; they just bring a particular class perspective to office.

But those differences in perspective lead to different decisions about the economic issues that affect all of us, decisions that have serious consequences. Social safety net programs are stingier, business regulations are flimsier, and tax policies are more regressive than they would be if our politicians came from the same mix of classes as the people they represent.

4) It's getting harder for lower-income and working-class people to influence our political institutions from the outside

Perhaps it wouldn't matter so much that working-class Americans are all but absent inside our political institutions if they had a powerful voice outside our political institutions. But that's not true either. For a host of different reasons, the voices of working-class Americans are getting harder and harder for politicians to hear.

Unions — which traditionally advocated the interests of lower-income and working-class Americans — have been shrinking for the last 50 years, thanks in large part to government policies that make it difficult for workers to organize.

Moreover, lobbying has become a multi-billion-dollar industry. And that's probably only the tip of the iceberg. The Center for Responsive Politics tracks lobbying at the federal level, but even its high-quality estimates miss all of the lobbying activity that happens through loopholes in the federal definition of a lobbyist and all the lobbying that happens in state and local government.

Elections are more expensive than ever. Want to be a member of Congress? You're going to have to raise millions of dollars. These days, being a politician is less and less about meeting with constituents and deliberating about legislation and more and more about approaching wealthy people, hat in hand.

A politician's most precious resource is their time. And all this fundraising takes a lot of time — and ensures that affluent politicians end up spending that time with affluent donors and lobbyists. President Barack Obama spoke eloquently about this in his 2008 book, The Audacity of Hope. "Increasingly I found myself spending time with people of means — law firm partners and investment bankers, hedge fund managers and venture capitalists. As a rule, they were smart, interesting people, knowledgeable about public policy, liberal in their politics, expecting nothing more than a hearing of their opinions in exchange for their checks. But they reflected, almost uniformly, the perspectives of their class: the top 1 percent or so of the income scale that can afford to write a $2,000 check to a political candidate."

The result is a kind of cognitive capture: the problems and opinions of affluent Americans loom large for politicians because they spend so much of their time around affluent Americans. Meanwhile, working-class Americans aren't inside our political institutions, and it's getting harder and harder for them to influence politicians from the outside, too.

5) Money and power is good at protecting money and power

The problem for reformers who want to make the government more representative of and responsive to blue-collar workers is that their efforts need to pass through our white-collar government.

Historically, reformers who have wanted to give the less fortunate more of a voice in our political process have focused on a) regulating donations to political campaigns, b) regulating lobbying, c) protecting workers' collective bargaining rights, or d) encouraging lower-income Americans to participate in politics in routine ways like voting or contacting their elected representatives.

Getting the money out of politics requires not just a policy that can foil the most expensive lawyers and campaign consultants money can buy, but the raw political muscle to make it happen — something that is nearly impossible to marshal when most lawmakers depend on big money to finance tomorrow's campaigns. (And don't forget about the Supreme Court.)

The same is true of efforts to promote unions or equalize routine political participation. As Jacob Hacker and Paul Pierson note, "We actually know how to increase voter turnout with relatively straightforward reforms" like same-day registration and early voting, but those reforms "have, not surprisingly, failed to gain traction within elite Washington." Supporting unions and increasing voter turnout aren't rocket science, but they aren't happening.

And why should they? These reforms ask politicians who are succeeding in the current political system to change that system so they're less likely to succeed in it.

That's the reality of the political "class war": the only people left to fight it are from the class that already won it.