U.S. President Donald Trump's order banning citizens of 12 countries from entering the United States goes into effect at 12:01 am ET (0401 GMT) on Monday, a move the president promulgated to protect the country from "foreign terrorists.

When Trump included Haiti in a list of countries on which he was imposing a near-total travel ban, some saw a culmination of a long campaign against the population.

Here is a closer look at why the administration says it is instituting full bans on foreign nationals traveling to the U.S. from 12 nations.