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!

Why aus DEM IRAN and aus DER TÜRKEI? There are two reasons. Firstly, "aus" takes the dative case, and the dative cases for der, die and das are: dem, der and dem respectively. der -> dem, die -> der, das -> dem. Secondly, Iran is masculine - "der Iran" and Türkei is feminine - "die Türkei" Some countries use the particle - "der Iran", and others do not - "Deutschland", "Frankreich".

Артем, названия стран в немецком языке могут быть разного рода, поэтому и нужно употребить соответствующий артикль в соответствующем падеже.