Normally we don't use articles with countries, but there are a few exceptions. A few of them are male or female and others are in plural. So, with "aus" we have to use the dative case, which is for male words "dem", for female "der" and plural "den".
Iran and Irak are male, so it is: aus dem Iran, aus dem Irak
Türkei, Schweiz are female, so it is: aus der Türkei, aus der Schweiz and
USA, Niederlande are plural, so it is: aus den USA, aus den Niederlanden.
You always have to check the grammatical gender, the case and the number (Singular or Plural) and you will never have problems ;)
Have still problems? Feel free to contact me!