SEATTLE — Federal law gives the president broad authority over immigration. Jimmy Carter used it to deny some Iranians entry to the U.S. during the hostage crisis, Ronald Reagan to bar Cubans who didn’t already have relatives here and President Barack Obama to keep out North Korean officials.

So why does President Donald Trump keep running into legal trouble with his efforts to freeze immigration by refugees and citizens of some predominantly Muslim nations?

When federal courts in Hawaii and Maryland blocked Trump’s revised travel ban from taking effect, the judges spelled out their major concern: the unusual record of statements by the president and his advisers suggesting the executive order’s real purpose was to discriminate against Muslims, in violation of the Constitution’s ban on officially favoring or disfavoring any religion.

As the legal fight moves into the appeals courts, two key issues will be the extent of the president’s broad immigration powers — and whether Trump’s own record stymies his plans.

Neither U.S. District Judge Theodore Chuang in Maryland nor Judge Derrick Watson bought the administration’s reasoning that the travel ban is about national security.

“The history of public statements continues to provide a convincing case that the purpose of the second executive order remains the realization of the long-envisioned Muslim ban,” Chuang wrote.

Watson criticized what he called the “illogic” of the government’s arguments and cited “significant and unrebutted evidence of religious animus” behind the travel ban. He also noted that while courts should not examine the “veiled psyche” and “secret motives” of government decision-makers, “the remarkable facts at issue here require no such impermissible inquiry.”

“For instance, there is nothing ‘veiled’ about this press release: ‘Donald J. Trump is calling for a total and complete shutdown of Muslims entering the United States,’” he wrote, referring to a statement Trump issued as a candidate.

But the scope of the rulings differed. In a challenge brought by Hawaii, Watson blocked the federal government from enforcing its ban on travel from six mostly Muslim countries and its suspension of the nation’s refugee program. Chuang only blocked the six-nation travel ban, saying it wasn’t clear that the suspension of the refugee program was similarly motivated by religious bias.

A federal judge in Seattle on Thursday ruled that his order blocking Trump’s original travel ban does not apply to the revised executive order because there are enough differences between the two.

Judge James Robart noted that Washington and several other states have also asked him to block the revised ban. He said he would rule on that request at a later date.