The Beltway is buzzing over President Obama's likely nomination of Thomas E. Perez as the next head of the US Department of Labor. But when Americans find out whom Perez has lobbied for most aggressively over the course of his extremist leftwing social justice career, they'll be wondering which country Obama's pick really plans to serve.

Press accounts describe Perez, currently the assistant attorney general for the Justice Department's civil rights division, as a "tireless advocate of worker and civil rights." The son of immigrants from the Dominican Republic, Perez was a former special counsel for the late illegal alien amnesty champion Sen. Ted Kennedy.

During the Clinton years, Perez worked at the Justice Department to establish a "Worker Exploitation Task Force" to enhance working conditions for...illegal alien workers. While holding down his government position, Perez volunteered for Casa de Maryland. This notorious illegal alien advocacy group is funded through a combination of taxpayer-subsidized grants (totaling $5 million in 2010 alone from Maryland and local governments) and radical liberal philanthropy, including billionaire George Soros' Open Society Institute.

That's in addition to more than $1 million showered on the group by freshly departed Venezuelan thug Hugo Chavez's regime-owned oil company, CITGO.

As I've reported previously, Perez rose from Casa de Maryland volunteer to president of the group's board of directors. Under the guise of enhancing the "multicultural" experience, he crusaded for an ever-expanding set of illegal alien benefits, from in-state tuition discounts for illegal alien students to driver's licenses and tax-subsidized day labor centers. Casa de Maryland opposes enforcement of deportation orders, has protested post-9/11 coordination of local, state and national criminal databases, and produced a "know your rights" propaganda pamphlet for illegal aliens that depicted federal immigration agents as armed bullies making babies cry.

The group can claim credit for pushing the White House to issue an estimated 800,000 illegal alien deportation waivers by executive fiat. And now, Casa de Maryland is currently leading the charge for an even broader illegal alien "path to citizenship."

Questioned by GOP Sen. Jeff Sessions during his DOJ confirmation hearing in 2009 about the illegal alien rights guide produced by Casa de Maryland, Perez grudgingly stated that "the civil rights division must not act in contravention to valid enforcement actions of our federal immigration laws."

But "act(ing) in contravention" of the law is at the heart of Perez's and Casa's radicalism -- and not just on behalf of illegal aliens.

During his tenure with the Obama DOJ, Perez sought to undermine electoral integrity by attacking South Carolina's voter ID law. His race card antics were rebuked by a unanimous US District Court panel (which included a Clinton appointee), and the law prevailed.

Perez was instrumental in covering the backsides of the militant New Black Panther Party thugs who menaced voters and poll watchers in Philadelphia in 2008. The American Spectator's Quin Hillyer recounted that a federal judge challenged the veracity of Perez's testimony about DOJ political appointees' interference on behalf of the Panthers. "This came after Perez also had, apparently unlawfully, refused to honor valid subpoenas from the US Commission on Civil Rights -- and it was in addition to yet another falsehood by Perez, this one to the effect that DOJ had sought the maximum allowable penalty against the Panthers," Hillyer reported. "While the original decision to dismiss the case pre-dated Perez's appointment to the Justice Department, his direct involvement in, and hands-on management of, what amounted to a cover-up of the decision's origins should alone be disqualifying for any Cabinet post."

Perez also helped spearhead the lawsuit against Arizona over its immigration enforcement measures and launched a three-year DOJ witch-hunt against Maricopa County Sheriff Joe Arpaio. The vengeful investigation against Arpaio, the nation's most outspoken local law enforcement official against illegal alien crime, was dropped without charges last summer. Perez is leading similar witch-hunts against police departments across the country based on leftwing junk science theories about racial "disparate impacts."

With Senate Republicans John McCain, Lindsey Graham and company folding like lawn chairs on Obamamnesty, open-borders groups are thrilled at the prospect of another victory with Perez's nomination. Last week, conservatives stood with Sen. Rand Paul, R-Ky., over John Brennan's nomination as CIA director. Who will stand for American workers in opposition to Obama's pending secretary of illegal alien labor? Anyone?