The justices will consider how much weight to give to Mr. Trump’s campaign statements. And they will act in the shadow of their own decision in Korematsu v. United States, which endorsed Roosevelt’s 1942 order and is almost universally viewed as a shameful mistake.
The Justice Department has worked hard to limit the damage from Mr. Trump’s campaign statements, which were often extemporaneous and rambling. It was hard to tell, for instance, precisely which Roosevelt policies Mr. Trump referred to or endorsed in his 2015 remarks.
“Impugning the official objective of a formal national security and foreign policy judgment of the president based on campaign trail statements is inappropriate and fraught with intractable difficulties,” Solicitor General Noel J. Francisco told the justices in a brief filed in February.
The challengers — Hawaii, several individuals and a Muslim group — took a different view. Mr. Trump’s order, they said, was “the fulfillment of the president’s promise to prohibit Muslim immigration to the United States.”
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.
In 1982, a congressional commission concluded that the internment of Japanese-Americans was “a grave injustice” animated by “race prejudice, war hysteria and a failure of political leadership.” It added that “the decision in Korematsu lies overruled in the court of history.”
But the Supreme Court has never overruled the decision. It remains, in the words of Justice Robert Jackson’s dissent, “a loaded weapon, ready for the hand of any authority that can bring forward a plausible claim of an urgent need.”
The supporting briefs in the new case, Trump v. Hawaii, No. 17-965, urged the justices to consider the similarities between the two executive orders. “Then, as now,” one said, “the government pursued a mass exclusionary measure of sweeping and senseless scope.” Both orders, the briefs said, relied on general characteristics like ancestry and nationality in the place of individualized scrutiny.
In defending the Japanese internment, the Justice Department told the Supreme Court that “the group as a whole contained an unknown number of persons who could not readily be singled out and who were a threat to the security of the nation.” Mr. Trump’s executive order bars entry of large numbers of people “about whom the United States lacks sufficient information to assess the risks they pose.”
In 2011, Neal K. Katyal, then the acting United States solicitor general, issued a “confession of error” for the actions of government lawyers in the Korematsu case. Mr. Katyal now represents the challengers in the case against Mr. Trump’s travel ban, and he may face an uphill fight next week. In December, the Supreme Court allowed the latest travel ban to take effect while the case moved forward, with only two justices noting dissents.
But there is little doubt that all of the justices view the case as momentous. On Friday, the court announced that it would release an audio recording of the arguments shortly after they end. That is a rare step, one the court reserves for cases likely to face historical scrutiny.