When low-wage, H-1B visa holders displace U.S. citizens, Congress is mum. But at the mere threat that illegal aliens designated as Deferred Action for Childhood Arrivals (DACAs) might lose their jobs, the most high-powered in Congress spare no effort to defend them.

More than 35 U.S. representatives signed a letter to House Speaker Paul Ryan, R-Wis., that demanded a DACA amnesty. And McClatchy reported that a senior Democratic legislative aide said, “DACA is priority 1, 2 and 3.”

Turn on any national news channel at any hour, and DACA dominates the reporting.

Yet, when H-1B visa holders displace Americans who have provided years of service and earned good performance reviews at Amazon, Apple, Disney, Google, Microsoft, Southern California Edison, the University of California and dozens of other institutions, it’s merely a footnote in the news, if that.

Congress certainly isn’t issuing any threats to shut down the government unless Americans get their jobs back.

Simply stated, American engineers lose their jobs because their replacements come cheaper. More than half of H-1B workers earn the Level One, basic skill wage.

As for industry claims that not enough qualified Americans are available to fill available IT jobs, recent studies by the respected, nonpartisan National Bureau of Economic Research, RAND Corporation and Urban Institute all found that colleges and universities graduate science and engineering students faster than businesses create jobs in those professions.

The expanding IT labor pool has stagnated salaries. Supply and demand dictates that if there were a domestic labor shortage, wages should increase. Instead, they’ve been flat, with many Americans holding STEM degrees unable to enter the field and a sharply higher share of foreign workers taking jobs in the information technology industry.

A look into how employers’ craven preference for cheap H-1B labor harms blacks, Latinos and women is telling. Last year, the St. Louis Post-Dispatch published a column, “Silicon Valley is using H-1B visas to crowd out American minorities.” Author Tom Broadwater, president of Americans4Work, wrote that the presence of H-1B visa workers has “especially hurt nonwhite, nonmale native-born Americans.”

One example is the story of Audrey Hatten-Milholin, a 54-year-old black woman who spent 17 years working in the technology department at UC San Francisco. Last February, UCSF laid off Hatten-Milholin and others, and then gave their jobs to younger, male H-1B visa holders from India. Eventually, the H-1Bs will return to India but continue to work for UCSF.

UCSF claims that H-1Bs represent a $6 million annual economic benefit. Critics note, however, that the $6 million total is a tiny fraction of UCSF’s $5.4 billion yearly budget, and that providing competent service to patients and doctors located in San Francisco from more than 8,000 miles away in India is impossible.

In November, Hatten-Milholin and several of her laid-off colleagues filed a discrimination suit against the university.

Although the Rev. Martin Luther King Jr.’s era preceded high tech, King’s biographer, close friend, speech writer and personal counsel, Clarence B. Jones, in his book What Would Martin Say? wrote that “Martin would be outraged by the greater immorality of importing a slave class into this country, especially one that has robbed so many African-Americans of their hard-won livelihoods …”

King’s historic 1963 “March on Washington” was officially named the “March on Washington for Jobs and Freedom.” But today, corporate America shuts out college-educated blacks from high-paying jobs in favor of cheap, imported labor, a disgrace to King and his legacy, which we remember and celebrate this month.

— Joe Guzzardi is a writer and researcher with Progressives for Immigration Reform who now lives in Pittsburgh. He can be reached at guzzjoe@yahoo.com, or follow him on Twitter: @joeguzzardi19. Click here to read previous columns. The opinions expressed are his own.

Joe Guzzardi is an Institute for Sound Public Policy analyst who has written about immigration for more than 30 years. A California native who now lives in Pittsburgh, he can be reached at jguzzardi@ifspp.org. The opinions expressed are his own.