But the broader point is that the Government has a duty to secure the borders. Why? To protect the people. And if the Government abandons its Constitutional duty, all citizens have the right to request the Courts to step in where the Government fails.
And say, that then happening, so what.
You might recall that President Jackson, when the SCOTUS ruled against him, said (to paraphrase) ... Well let's see them enforce that ruling.
Today, in the United Stares, politics and not law rules.