The Supreme Court is letting the Trump administration mostly enforce its 90-day ban on travelers from six mostly Muslim countries, overturning lower court orders that blocked it.
The action Monday is a victory for President Donald Trump in the biggest legal controversy of his young presidency.
Trump hailed the decision as a "clear victory for our national security."
In a statement, Trump said his "number one responsibility" is to keep the American people safe.
The ban on visitors from Iran, Libya, Somalia, Sudan, Syria and Yemen can be enforced as long if those visitors lack a "credible claim of a bona fide relationship with a person or entity in the United States."
The court did leave one category of foreigners protected, those "with a credible claim of a bona fide relationship with a person or entity in the United States," the court said in an unsigned opinion.
Local 10 News reporter Shyann Malone spoke Monday to travelers at Miami International Airport about how they felt about the ban.
"I think it will be a good thing," Heath Herring said. "They need to do it for a lot longer than 90 days, that's for sure."
Others weren't so thrilled with the news.
"I am horrified. It just worries me," Peter Rigler said.
The first time the travel ban was announced, MIA saw backed up customs lines, which delayed passengers from getting through checkpoints in a timely manner, as travelers were randomly pulled aside and questioned.
"The problem was it went into effect immediately," U.S. Rep. Ileana Ros-Lehtinen, R-Florida, said. "There was no training for those on the ground as to how to process individuals from those countries, so there was chaos."
Ros-Lehtinen isn't in favor of the ban, but said we shouldn't see the chaos that it created last time.
"You will have protests, you will have people saying it's unfair, but it should be implemented in an airport in a far smoother way, because now they know what they've been dealing with for many months," she said.
Loretta Westin, a resident of the Cayman Islands, said implementing restrictions on travel makes sense.
"I think targeting countries that are particularly messed up -- and also known to be violent against the west -- for a short term while they figure out whether or not they have a good system for vetting in place makes sense," Westin said.
Others told Local 10 the ban was discriminatory.
"As an immigrant -- I actually don't fall into the categories being banned -- but I still believe that's not the solution to the problem (the president is) stating we have," said Alberto Garrido.
The justices will hear arguments in the case in October.
Trump said last week that the ban would take effect 72 hours after being cleared by courts.
The Trump administration said the ban was needed to allow an internal review of the screening procedures for visa applicants from those countries.