It's just the beginning.
I won't pour over the exact details of the ban, you can read the official release instead (see link below). A quick glance of the list of countries it effects (Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen) might have you believe the Executive Order is genuinely about "Protecting the Nation from Foreign Terrorist Entry into the United States". Now that terrorists are banned, they are certain to stop entering the country, right?