My hometown of Fresno, Calif., is the epicenter of that state’s annual $47 billion agriculture industry. The money flows from the sale of the valley’s citrus, nuts, stone fruit, tomatoes, grapes, olives, dairy delights produced by many tens of thousands of cows and other staples of our diet too numerous to list.

Crops do not harvest themselves. An article in the New York Review of Books last month estimated that 80 percent of California farmworkers are undocumented Mexican citizens. It is impossible to envision precisely how decimated California’s economy would be without that labor force (and therefore the American economy, as California’s economic output is by far the nation’s largest). But it seems safe to assume such a scenario would be devastating.

As the home of Big Agriculture, California is an easy entry point for considering this. But zoom out and survey the entire U.S., taking in other states’ farming economies, hospitality industries and the unmeasurable pile of money exchanged under tables for domestic help.

Around the country, undocumented workers are not just moving our food from fields to grocery stores for our easy, affordable access, but also washing and cooking it in the kitchens of American restaurants, cleaning our homes, landscaping our yards, scrubbing toilets in and the public buildings where we work and play and providing childcare so we can go earn our paychecks.

Unsurprisingly, undocumented workers perform the most demanding physical tasks in the least hospitable conditions — picking tomatoes in summer’s 110-degree days and slinging chemicals to eradicate grime through night shifts. It’s generally work many U.S. citizens are unwilling to do.

These workers aren’t prospering or even achieving middle-class status. They aren’t soaking us for perks and benefits. They are merely surviving, trying to keep shelter overhead and food on their tables — and they’re propping up our economy in the process. Anyone who believes that Americans’ quality of life would not fundamentally decline if undocumented workers suddenly disappeared lacks basic information about their role here.

That makes the whole “We need a wall” business that much more offensive. Of all the racist, ignorant actions and statements emanating like poison gas from the clown posse in Washington, fear-mongering around the wall could be the most dishonest.

Rather than a wall, what we actually need are revolving doors and express lanes. If the economic facts regarding Mexico’s role in our economy were stripped of politics and fear-mongering and laid out objectively, I’ll bet we’d find ourselves on a path to an AU — an American version of the European Union — with borders safely and efficiently navigated by those on either side, common passports and currency, mutually beneficial trade agreements, public transportation and affordable housing to support the flow of workers, students and others across borders. (Why not dream big?)

Imagine the boon to both countries’ economies: For us, we’d enjoy less labor turnover and greater productivity stemming from workers’ improved mental and physical health. (When you’re not living in utter terror in cramped, dire conditions, you’re likely to be better at your job). Mexican workers would see increased opportunity and economic mobility that would ripple outward through their country.

I’m disappointed in our Democratic leaders in Washington for not better explaining the truth of undocumented workers’ value. The political discourse seems stuck at a kindergarten-level, “Immigrants bad. No, immigrants not bad.”

It wouldn’t be a terribly complex proposition to explain undocumented workers’ role in our economy. Lawmakers, perhaps you could develop those talking points just a bit? The ongoing scapegoating and demonizing of hardworking people who we rely on is shameful.

Discussing how immigrant labor benefits us economically leaves aside a plethora of honorable, compelling reasons to welcome those who seek work and life here — human rights crises, for example. And I believe strongly in granting asylum to those in need just as I would want asylum granted to me if I was in need.

But if for no other reason than their essential contributions to our country’s functioning, Mexican citizens should be welcomed, celebrated and supported here.

Michelle Martin Deininger

Michelle Martin Deininger, Park City, is a freelance writer and former newspaper reporter and editor. She blogs at www.moonlightmile.blog