A pair of supporting briefs, from children of Japanese-Americans held in the detention camps and several public interest groups, went further. They said Mr. Trump’s latest travel ban is of a piece with Roosevelt’s order.
“History teaches caution and skepticism when vague notions of national security are used to justify vast, unprecedented exclusionary measures that target disfavored classes,” lawyers for the Japanese American Citizens League told the justices.
There are, of course, major differences between the two orders, as legal scholars have noted. Roosevelt’s order applied to people living in the United States, many of them citizens, while Mr. Trump’s order concerned nationals of other countries living abroad. (The countries initially included Iran, Libya, Syria, Yemen, Somalia, Chad, North Korea and Venezuela. Last week, the administration lifted restrictions on travel from Chad.)
In enforcing Roosevelt’s order, moreover, the military singled out “persons of Japanese ancestry.” Mr. Trump’s order, by contrast, is neutral on its face, though it disproportionately affects Muslims.
Still, the legacy of the Korematsu decision figured in opinions in recent appeals court decisions blocking Mr. Trump’s third and most considered travel ban, issued as a presidential proclamation in September.
The Korematsu decision occupies a curious place in the Supreme Court’s jurisprudence, as a grave error that has never been formally disavowed.