'US visa holders should know...': What Marco Rubio's statements on revoking visas mean

Marco Rubio explained in his opinion piece for Fox News that once a visa is granted, it is not forever. The US government's rigorous security vetting does not end once a visa is granted. And evert US visa holder should know this, Marco Rubio said. "Working together with DHS and other law-enforcement and security agencies, we continuously monitor and review these cases. This vigilance is essential because circumstances can and do change," he wrote.