Editor's Note: Eric Garcetti is the mayor of Los Angeles and a former president of the Los Angeles City Council. The views expressed in this commentary are solely his.
(CNN) - Not long after her husband was killed in the Mexican Revolution, Guadalupe fled north with her 1-year-old baby son in her arms. More than a century ago, she crossed the border and arrived in America without immigration documents -- or much else.
Years later, her son Salvador volunteered for and fought in World War II, earned his citizenship through military service, and eventually opened a small business -- a barber shop in South Los Angeles. Salvador was a Dreamer before the term existed -- and he was my grandfather.
My family story isn't unique in this nation of immigrants. And today's Dreamers -- who are American in every way except the papers they hold -- have the same potential and drive to serve their country as my grandfather.
But there's an important difference: Young people brought to the US as children are confronting the prospect of deportation now from the only country they've ever really known.
This is not only cruel -- it's nonsensical.
There are currently about 690,000 Deferred Action for Childhood Arrivals (DACA) recipients nationwide -- and more than 89,000 here in the L.A. metropolitan area.
If we send all of these young people back to the countries where they were born, our nation's GDP could lose up to $460 billion over the next decade. Here in California, our state GDP stands to lose an estimated $11.6 billion per year.
Dreamers are helping to build this country. We need them to continue learning and teaching in our schools, serving as first responders, working in our laboratories and factories, and wearing our nation's uniform in the armed forces. The Labor Department already announced record job openings this summer, which indicates that US companies are struggling to find qualified workers. If we end the DACA program and forfeit all those talented young workers -- and their spending power -- our economy will suffer.
Dreamers are young people I've gotten to know like Maria, a college student and aspiring lawyer who was brought to this country from Bolivia at the age of 6; and José, a 7th grade math teacher who wasn't even 2-years-old when his family left Mexico for California.
Maria and José belong in this country, and have so much to contribute. It's our responsibility, and in all of our best interests, to keep them here with their families and to call on Congress to pass the bipartisan Dream Act.
If our leaders in Washington do the right and compassionate thing, it will follow the broader work we're doing in L.A. -- and cities across America -- to protect people from being separated from people they love and expelled from communities they helped build: We're fighting in federal court to protect DACA, connecting immigrants with legal aid when they're faced with deportation, hosting events to make immigrants more aware of their rights under the Constitution, and even using our libraries to help people navigate the naturalization process and get on the path to citizenship.
There is both a moral and an economic argument to allowing Dreamers to stay in the US That's why Americans from across the country have called on Congress to protect them, from former Secretary of Defense Robert Gates to tech and business leaders, including the CEOs of Apple and JP Morgan Chase.
Not only that, a majority of voters, 82%, want legislation protecting Dreamers from deportation.
We need to preserve our role as a place of opportunity. And today, as we kick off the DACA Day of Action, millions of Americans are taking part in a campaign on social media to send the message to Washington that we want them to protect the Dreamers.
The stakes couldn't be higher: America is great because of people like my grandfather, Maria, and José -- Americans who want to work hard to build a life in the only country they call home. We don't want to lose them, and we can't let them down.