So far, the Supreme Court has not ruled squarely on Trump's broad assertions of power. But the justices have granted a series of emergency appeals from Trump's lawyers and set aside lower court orders that blocked his initiatives from taking effect.

The court's decision left enough room for the challengers to Trump's directive to try to prevent it from taking effect while litigation over its legality plays out.

Using truncated procedures, the six-justice conservative majority gave a green light to many of the president’s most assertive initiatives.