The ongoing march of ISIS (Islamic State of Iraq and Syria) in Iraq is a major threat to Iran’s security.
ISIS is fanatically Sunni and they especially loathe Shias. Iran is Shia.
Victorious now in Ramadi, ISIS is now just 65 miles from Baghdad. South of Baghdad is Karbala, the holiest city for Shias.
The notoriously corrupt Iraqi army has not been able to hold back the advance of ISIS. Given the threat ISIS poses to Shia Iran Tehran has already shown its determination to defeat this Sunni aggression in Iraq. This will increase in the coming weeks.
This show down between Shia Iran and Sunni ISIS underlines for every Muslim the deep divisions that exist in their faith. This confrontation could bring further disillusionment with Islam and a longing for the Prince of Peace.