April 15 is Tax Day. For many of us, it also is a reminder of the disparity between what working people pay in taxes versus what the 1 percent pay.

The unfairness of our system is best illustrated by billionaire investor Warren Buffet, who pays a lower tax rate than his secretary. To Buffet’s credit, he continues to call for higher taxes on the super-rich. Unfortunately, he’s the rare exception. Those who write the tax laws listen to, and do the bidding of, the billionaire class.

The unfair tax structure is related to an even bigger issue: wage stagnation. Real wages for the vast majority of U.S. workers have declined or held still since 1979. And that’s not because workers are slacking off. During that same period, says the Economic Policy Institute, productivity in the nation has risen by 64 percent. This disparity between productivity and wages amounts to wage theft on a grand scale.

We’re going to do something about it. April 15, people from all walks of life will join hands with low-wage workers to press the Fight for $15, calling for a $15-per-hour minimum wage, better working conditions and the right to form a union without retaliation from bosses.

That fight, which began with fast-food workers in 2012 here in New York City, has gained nationwide momentum, drawing low-wage workers from many industries. But the Fight for $15 is not just about low-wage workers. It’s about lifting the wage floor for all workers and strengthening our economy and our communities.

1199SEIU will be out in force April 15. We will be marching shoulder to shoulder with our homecare members, too many of whom struggle mightily to make ends meet although they perform one of the most important services in our nation.

Home care is the fastest growing segment of our nation’s fastest growing industry—health care. As the baby boomers retire, they increasingly require assistance from a qualified and stable work force. Continuing to underpay home care workers is a disservice to both the workers and the seniors and disabled persons they care for.

The late Martin Luther King Jr., the touchstone for 1199SEIU and so many others, was assassinated 47 years ago on April 4, 1968. At the time, he was launching the Poor People’s Campaign, which he called phase two of the Black Freedom Movement—from civil rights and voting rights to economic equality.

His support of low-paid sanitation workers in Memphis was the first round of that campaign. “What does it profit a man to eat at an integrated lunch counter if he doesn’t earn enough money to buy a hamburger and a cup of coffee?” King asked in Memphis days before his death.

Three weeks earlier, King spoke at a New York City meeting of 1199, at which he described his campaign for the “other America,” where “people work full-time jobs for half-time pay.”

We can best honor our fallen leader by grabbing the torch and continuing his campaign. That means raising the wage floor. That means changing policies that favor the 1 percent, such as anti-worker business practices, including the suppression and outlawing of unions. That means boosting our economy by creating jobs and repairing our social safety net.

We can begin by repairing our failing infrastructure and building and staffing our public institution, such as our health care facilities and our schools. Paying all workers a living wage would do far more for our economy than continuing to stuff the pockets of billionaires, who offshore their earnings and investments. Today, the 80 richest people in the world control more wealth than the poorest half of the world—3.5 billion people.

And New York City is no exception. Working people here find it increasingly difficult to make ends meet. This inequality snuffs out opportunities for our children, drags down our economy and weakens our democracy. That is why all New Yorkers need to join the Fight for $15 on April 15. The campaign is not only a fight for economic equality, but also a fight for justice. And as King reminded us, “When you stand up for justice, you can never fail.”