Aiming at both Central American labourers and Indian tech workers in Silicon Valley, the US administration is ramping up a crackdown on undocumented immigrants encouraged by a sharp downturn in illegal border crossers.
Police, prosecutors and judges have been ordered to take a harder line against all illegal immigrants, detaining anyone without papers and vigorously prosecuting more of them.
Hiring standards for immigration agents are being eased to quickly beef up their ranks, more facilities to hold detained immigrants are being built, and more judges are being added to handle cases.
And officials have been directed to round up illegal immigrants, even those in the country for decades, at places that used to be safe - court houses, town halls, and cities offering them sanctuary.
Meanwhile designs are underway for construction of a wall along the entire 3,200-kilometre US-Mexico border that President Donald Trump promised. It won't be a full physical barrier all the way along, but strategically erected wall sections interspersed with stretches of technology-dependent surveillance.
"For those that continue to seek improper and illegal entry into this country, be forewarned: This is a new era. This is the Trump era", Attorney General Jeff Sessions told border patrol agents on Tuesday.
Trump came into office promising to expel the estimated 11 million people living in the United States illegally, who he says steal American jobs and fuel crime. Most are from Mexico, and many of them have been here for decades, raising families, owning homes and businesses.
Three months into the Trump administration, the number of illegal border-crossers has plunged to a four decade low, according to the Customs and Border Protection agency (CBP).
Apprehensions of illegal border crossers in March dropped to 16,600, down 30 percent from February and 64 percent from a year ago.
It is too early to see any pickup in deportations, which take longer to process. But Tom Jawetz, vice president incharge of immigration policy at the Center for American Progress think tank, says there is a clear change in immigration enforcement.
Sessions this week ordered CBP and Immigration and Customs Enforcement (ICE) to detain anyone who crosses the US-Mexico border without legal documents and present them to a judge. In the past, most were just delivered back over the border.