The Supreme Court will hear my case today. Trump will not win on DACA.

I will not live in fear. And neither will the 700,000 undocumented immigrants like me.

Two years ago, when President Donald Trump moved to end the Deferred Action for Childhood Arrivals program, I said, “I’ll see you in court, Mr. President.” Now, the case that bears my name, McAleenan v. Vidal, is one of three consolidated cases that has reached the highest court in the land. On Tuesday, the Supreme Court will hear oral arguments on which my future hangs.

As a person who depends on DACA to remain in...