For hundreds of thousands of people every year who dream of studying or researching in the United States, a student visa is the golden ticket.

Secretary of State Marco Rubio said last month that he's revoked at least 300 visas of students he described as "lunatics," citing pro-Palestinian support or activism, activities that are normally considered protected First Amendment rights, USA TODAY reported.

More than 1,000 international students at 128 colleges and universities have had their visas revoked or their legal status terminated since mid-March.