Why did plantation owners think they needed slaves

In 1944, the supreme court upheld the authority of the u. s. government to order the internment of a minority group in the interest of national security, even though there was no evidence that any members of this group were disloyal to the united states. should the same policy be applied today against u. s. muslims or muslim immigrants? why or why not? are these forms of internment different from native reservations? if so how? if not, why?