The U.S. high tech sector is the envy of the world in no small part due to the contributions of immigrant scientists, engineers and entrepreneurs. Yet making

their—and their employers'—lives miserable has become a top priority for the Trump administration.

Almost since day one, restrictionists in President Donald Trump's inner circle targeted not just undocumented low-skilled workers but also legal high-skilled ones. And the latest in their crosshairs may be international students—the very people who Mitt Romney, during his ill-fated presidential campaign, said should have green cards stapled to their diplomas, since it makes no sense for them to get an American education and then return to their home country to compete with America.

The White House's "Buy American and Hire American" executive order, drafted largely by restrictionist Trump aide Stephen Miller within months of Trump assuming office, ordered the Department of Homeland Security and other federal agencies to "rigorously enforce and administer the laws governing entry into the United States of workers from abroad" with an eye toward creating "higher wages and employment rates for workers in the United States." And the agencies aren't wasting any time. They have been scouring and revising existing rules to make it as hard as possible for high-skilled immigrants to come—and stay—in the United States. Here are just a few of the things they've done:

The U.S. Citizenship and Immigration Services (USCIS) just last week instructed its adjudicators to no longer "defer to prior determinations," approvals and findings of facts for the renewal of H-1Bs and other high-skilled visas. This means that when high-tech foreigners try to extend their H-1B after three years, the government having previously approved their applications—involving the same set of facts—means nothing. For employers, it will create uncertainty and additional paperwork burden.

USCIS is also issuing 'exponentially more' of what are called "requests for evidence" when an employer first petitions for an H-1B visa, according to BNA Bloomberg. This means that employers must submit additional evidence regarding salaries and job duties so that the agency can ensure that H-1Bs are being handed only to the "most-skilled or highest-paid."

USCIS adjudicators are also far more suspicious of H-1B petitions where employers offer the lower end of the prevailing wage spectrum, for example when hiring fresh graduates with less job experience. They think that that's an indication that the individual's position isn't sufficiently complex to qualify for a visa.

The Trump administration is delaying whether to defend a regulation that allows certain spouses of H-1B visa holders to work. Tens of thousands of qualified spouses are currently locked out of the job market because their visas bar them from working.

But what's sending fear and trembling in the high-tech community is an expected rule change that will eliminate the STEM OPT (Optional Practical Training) program that the Bush administration first implemented. "Work inside the agency to rescind the STEM OPT regulation has already begun," according to Lynden Melmed, a partner at the immigration law firm Berry Appleman & Leiden. "Right now, it is not a question of whether the administration will walk that path. It is just a question of when."

This program allows about 45,000 new foreign STEM (Science, Technology, Engineering and Math) students annually to work in the country after graduation not just one year, as is the case with non-STEM students, but three. This adds an important "practical" aspect to their education and gives them much-needed time to land jobs and stay in America via an H-1B. Otherwise, America would lose a wealth of talent to other countries.

But the Trump administration has had its sights on eliminating this program for a while. The only reason it might be dithering is that the case for doing so is extraordinarily weak.

For starters, unlike the DACA (Deferred Action for Childhood Arrivals) program that the Obama administration implemented without a federal regulation, STEM OPT was properly constituted. It was conceived under President Bush and extended by President Obama.

"In 2016, the Department of Homeland Security (DHS) legally expanded OPT to include an additional STEM extension, and the agency properly followed the notice and comment requirements of the Administrative Procedure Act to expand OPT for STEM students," Stephen Yale-Loehr, a professor of immigration law practice at Cornell Law School explains. "A federal court dismissed a challenge to the DHS's STEM OPT extension rule, providing further assurance of its legality. Thus, the current administration cannot argue that the existing rule was promulgated illegally."

If the legal case for eliminating STEM OPT is dubious, the economic rationale is non-existent.

In the absence of STEM OPT, American companies that want to hang on to these students will hire them and place them outside the United States. "Without an H-1B program supported by the current STEM OPT option, Cummins and other employers will be forced to move our employees and their jobs outside the U.S.," said Lorrie Meyer, executive director for global talent management at Indiana-based manufacturer Cummins Inc. This would mean pushing both innovations—and related jobs—to other countries. That is the opposite, of course, of the goal of "America First."

But that's not the only economic downside of ending STEM OPT. If foreign students can't work in America after graduating, they'll be less likely to enroll in American universities in the first place. "Eliminating STEM OPT would have a chilling effect on international students, causing many to rethink applying to U.S. universities," Jackie Bangs, assistant director, Division of International Programs, Oregon State University notes.

According to the National Science Foundation, international students currently account for 81% of the full-time graduate students in electrical engineering and 79% in computer science at U.S. universities. My organization's research found that international students make up more than half of the full-time enrollment in about 90% of U.S. graduate level programs in computer science and electrical engineering. Many schools have fewer than 30 full-time U.S. graduate students in their science and engineering programs because many Americans have been eschewing these fields.

Without international students, therefore, there simply wouldn't be enough students to sustain a full range of graduate level STEM course offerings, which would shrink the choices for U.S. college students. There will be a net retrenchment in STEM in higher-ed, which will mean that America will graduate even fewer American STEM students than it currently does.

Fewer international STEM students will also make it harder to attract and sustain high-level faculty members who need them to assist in research. "At the graduate level, international students do not crowd-out, but actually increase domestic enrollment," according to research by economist Kevin Shih. "Foreign student tuition revenue is used to subsidize the cost of enrolling additional domestic students."

Besides the impact on universities, no credible economist thinks that kicking out Master's and Ph.D.'s in science and engineering fields is good for an economy. These students are easing a tight labor market, not displacing Americans, given that U.S. students in STEM fields earn far higher salaries than their peers, reports the recruiting site Glassdoor, and jobs are plentiful in computer fields, according to the Conference Board.

Furthermore, eliminating STEM OPT flies in the face of the administration's own claim that it wants to make America's immigration system more "merit-based." If high-skilled foreign nationals trained in STEM fields in America can't qualify for visas, then who can?

The administration's assault on high-skilled foreigners and international students is the clearest indication that its immigration agenda is not motivated by a concern for American jobs or the American economy. This won't Make America Great Again. It'll do the opposite, in fact.

Stuart Anderson heads the National Foundation for American Policy, a think tank that focuses on immigration and trade issues.