USA has it. EU has it and Russia as well so does Japan and China and India.
Basic fact is that you can´t reach orbit with out it. Using a "liquid fuel engine" is very complex and i don´t see how Iran could manage this technology. I also don´t see any RCS and OMS engines ...
I also don´t see the higher goal in this project. What does Iran try to achieve with this? Iran is too small to go into interplanetary missions, too small to build a space station and so on.
Too put things into proportions.
Irans entire GDP this year is 368 Billion $.
This is Endeavour...
The Construction of Endeavour alone did cost 16 billion $...and there are also Columbia, Challenger, Discovery, Atlantis...So all 5 Orbiters combined did cost 80 billion $. Thats almot 1/4 of Irans annual economic output.
Each launch of a shuttle cost an additional 1.5 billion $...
Now some may say: well a gigantic spaceplane is expensive...
But lets go to the ESA Ariane V
Ariane V is a very powerful and popular rocket. Each cost 180 million $.
Now whats the budget of the iranian space program?
In 2014 it was 71 million $... thats not even a half Ariane V.
Now one may argue that Iran can not play in same league as NASA / ESA or Roskosmos...But indias Mars Mission alone did cost 70 million...We are talking about a single mission here.
To bring things even more into perspective. Iran could not even buy an A320 regional jet with its entire space budget...