There are many reasons to fire Wisconsin Gov. Scott Walker (R) next Tuesday. But some people in Wisconsin and others who are following the recall battle between Walker, who last year eliminated the collective bargaining rights of 380,000 public employees, and Milwaukee Mayor Tom Barrett (D), who supports workers’ rights to bargain, are asking:

What’s so important about collective bargaining in the first place?

Let’s start with the fact that collective bargaining builds and protects the middle class, not just for union members, but for all workers. Here’s how.

Companies and other employers don’t just hand out fair wages and better benefits, even to employees they say they value. Middle-class wages and benefits like health care and paid sick days are built over time by working people who come together to insist on fair standards.

Through their unions, working people bargain collectively with employers—both private and public—to determine their terms of employment, including pay, health care, pensions and other benefits, hours, leave, job health and safety policies, ways to balance work and family and more.

Raising standards in an industry affects other workers in the industry, too, even if they aren’t part of a union. As the American Worker Project pointed out in its 2011 report “Unions Make the Middle Class,” collective bargaining draws the map for all workers to get to the middle class.

In America today, states with higher concentrations of union members have a much stronger middle class. The 10 states with the lowest percentage of workers in unions all have a relatively weak middle class.

Let’s not forget another basic fact about collective bargaining. It is an internationally recognized core workers’ right. The United Nations Universal Declaration of Human Rights calls it an “enabling” right—a fundamental right that ensures the ability to protect other rights.

Collective bargaining also provides a check and balance to employers’ power—and yes, cities, counties and states are employers. You really can’t expect every worker to bargain his or her own terms of employment. Without collective bargaining, employers can and do unilaterally impose their own terms and conditions.

Then we have the cold hard political reasons why collective bargaining is so damn important, especially for public workers like the 380,000 Wisconsin teachers, health care workers, snow plow drivers, social workers and more.

Politicians like Walker and others in the past couple of years who have attacked workers’ rights claim they are simply trying to curb spending and arrest state budget problems by eliminating collective bargaining.

But just a little closer look makes it clear they want to limit the power of working people, balance budgets on the backs of working families and deliver political pay-back to corporate and wealthy campaign contributors.

In Walker’s case, the elimination of collective bargaining was part of a package that included tax cuts for corporations and the wealthy and drastic cuts to health care, education and other vital working family programs. It’s no surprise that Walker’s close allies such as the extremist American Legislative Exchange Council (ALEC), the far, far right-wing Koch Brothers and other corporate and anti-worker groups so passionately back Walker.

You could even make the case that collective bargaining is a core conservative principle. In 1968, then-California Gov. Ronald Reagan (R) signed a law granting public employees collective bargaining rights. Who’s more core conservative than Reagan? Of course, he changed his tune as president, but that’s another story.

There are many reasons to fire Scott Walker next Tuesday and his attack on collective bargaining is a pretty good one.