But when President Donald Trump announced Tuesday that DACA would be eliminated in six months, the company responded that it had no bigger legislative priority than persuading Congress to protect the so-called Dreamers. “There is nothing that we will be pushing on more strongly for Congress to act on,” said Microsoft president Brad Smith. That includes tax reform, which could save the company billions of dollars on its future bills to Uncle Sam.

Microsoft’s reaction—and that of other successful technology companies like Facebook, IBM, Apple, Cisco, and Google—comes not just from concern over the fate of young people who could now be deported back to countries most of them left as small children, though that is no doubt genuine. It comes because these companies understand that U.S. openness to the world’s best and brightest immigrants is a big reason not just for their success but for American leadership in almost every high-technology sector. The elimination of DACA—and the larger war on immigrants launched by the Trump administration—gravely threatens that success.

Most Americans do not appreciate the unpredictability of our immigration system. Rigid quotas and often arbitrary rulings by government bureaucrats and immigration judges have profound effects on the futures of those who choose to try to make their lives in the U.S. Despite this byzantine system, which has not been overhauled in a meaningful way since 1965, talented immigrants continue to flock to America, drawn by the enormous economic opportunities still on offer here.

But the companies are rightly worried that the U.S. could lose its standing as the destination of choice for smart immigrants. Already, the failure by Congress to reform immigration laws has left many highly skilled immigrants in limbo, working on temporary visas and waiting years for green cards. The Obama administration tried to sweeten the offer in the absence of congressional help—including allowing spouses of H-1B workers to hold jobs, expanding the Optional Practical Training program that authorizes foreign students to work after they graduate, and permitting foreign entrepreneurs who start companies to remain in the U.S. The Trump administration, however, has signaled it may undo all three initiatives.

What most worries the companies about the elimination of DACA is the message that sends to all would-be immigrants—that the U.S. is becoming an unfriendly and uncertain place in which to try to build a future.

The strong corporate opposition to Trump’s travel ban, which was targeted at a handful of Muslim countries, was similarly not because companies had many employees who would be directly affected, but because of the message it sent to the world. As Apple and other tech companies said in their brief opposing the travel ban, it would “make it more difficult and expensive for U.S. companies to recruit, hire and retain some of the world’s best employees.”

The DACA rescission is especially capricious and damaging. DACA offered young immigrants—who took a great risk in coming forward and registering with the government—some stability and hope for the future, only now to see it suddenly ripped away. And these are exactly the sort of immigrants American companies want to keep. Ninety-three percent have graduated from high school and a third are either college graduates or currently enrolled. Nearly 90% are employed, and most are bilingual and in many cases multilingual.

Trump’s actions will now throw the issue to Congress, where the decade-long failure to reform immigration laws cannot be cause for optimism. But perhaps lawmakers will finally recognize that the stakes are enormous. It is not just about the Dreamers themselves; it is about whether the U.S. will remain the most dynamic and innovative economy in the world.

Edward Alden is a senior fellow at the Council on Foreign Relations, and was project director for the CFR Independent Task Force on U.S. Immigration Policy.