One of the key cases in modern Constitutional Law is Korematsu v. United States, where the Supreme Court held that the exclusion of Japanese citizens from large parts of the West Coast was constitutional. (While the case technically did not cover the internment of the Japanese, the exclusion of Japanese from such a large area without any individualized suspicion renders both internment and exclusion to be largely subject to the same analysis that I make here.) This case is normally thought to represent an egregious failure on the part of the Supreme Court to enforce constitutional law.
But things are more complicated than they at first seem. To begin with, the normal argument is that the Supreme Court should have struck down the exclusion and internment as a violation of the Equal Protection Clause. But the Equal Protection Clause does not apply to the federal government. For that reason, the major nonoriginalist critics of Korematsu argue strenuously that the Equal Protection principles are somehow reverse incorporated or otherwise applied to the federal government. That ignores the text and is a mistake. For more of my views on the matter, see here.