Yes: in 1953 the CIA and UK intelligence services mounted an operation to give Mohammad Reza Pahlavi a coup d'stat to act in their interests. That was overthrown in 1979 - and Iran have been building up a stash of weapons since then against clearly hostile countries to them.
Well, what a surprise - typical, the West tries to "fix" and other country and in the end ......makes it worse than it might have been.
They are not a "Terrorist State". They are a very complex and broad society, a well developed middle class and intelligentsia. Power in terms of state institutions is held from the top and enforced by the Revolutionary Guard, but there are millions of "non terrorists" in this actually very sophisticated society with many highly educated people from this Persian culture..
(Yes I do know Iranians in the UK who have family in Tehran and know what is going on and what has going on)
Its suits the US and those who support this line of thinking in order to accept so called "collateral damage"
but I'm not buying it.