I don't think our little friend here quite understands the other view of things.
Nobody denies innocent people are being shot and massacred, the point is that they are shot and massacred by Salafist herds. who have so far also murdered over 100s Shia, police, military and christians, this is no convenient coincidence, this happens all over the arab world where wahhabism from Saudi Arabia (a backward ideology that challenges the traditional four schools, two of whom have interwoven ideological motives with the Shia, and must be 'reformed') is on the rise among Sunnis, especially where literacy and civil society is low. Also, as we saw from the interview with Webster Tarpley, who has been to Syria, people in places like Der'aa are scared to death of snipers randomly shooting people to frame Assad for the crime, a typical CIA tactic used all over Latin America and even 2009 Iran by opposition forces to overthrow governments through US black ops.
The people who oppose Assad, oppose him for all of the wrong reasons. Their motivation is not freedom or democracy, but that Assad is a Shia, and of course, Shia are jews, kuffar, untrustworthy, wretched and worthy of killing and must be driven out from Syria. Imam Hassoun, also a Salafist has taken a worthy stance against this ignorance, and has supported Assad, he is the main leaders of Sunnism in Syria, and has shown exceptional courage in stating that he was approached by these thugs, he wanted them to explain why they wanted to overthrow Assad, and they could not give a coherent answer to him, so he rejected their backward movement.
The only crime by Syria is that it has not taken the route of North Korea, and instead, throughout the years Syria has been a place where Wahhabis from Afghanistan and Iraq returned, but also where US operatives were free to carry out spy activity.
Iran has every right to react, and not take it lightly.