Of the 12 countries from which travel is fully restricted, three are embroiled in bloody civil wars. Many of the other countries are also undergoing conflicts.

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.

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.