Iran high? I wasn't aware of that. Could I ask what you are basing that on. Do you mean Iranian militias which are effectively the army and doing things which could be said to protect their country (as with US soldiers in all kinds of places they probably shouldn't be). If so I don't think that comes under the heading "angry young jihadis"
Iran has backed many jihadist groups. Two examples: Hamas, they are a group against Isreal which receives support from Iran. Iran also backed the Shiite "Mahdi army" during the Iraq war which fought a jihad against American/coalition forces, and today are still involved in a 'defensive jihad' against IS.
There are other examples. Jihad has been fought by both Sunni and Shiite groups. But more so by Sunni groups such as IS and AQ - who have tended to have more of a global objective against the west. While Iran and Shiite groups (such as in Syria/Lebanon) are mostly interested in local power grabs to keep spreading their Islamic Revolution outside of Iran.
I highly recommend this New Yorker piece on Iran and their secret proxy wars:
You're shifting the topic. We're talking about how many young Iranian men become terrorists, not the support of various groups by the Iranian state.
Most nation states, certainly including the USA, have at one time or another given material and financial support to terrorist groups. I don't condone it, but Iran is hardly exceptional in that regard.
