God - be glorified - punishes the idolaters and associaters who associate their idols and other gods besides God Almighty the Creator.
One kind of punishment that He afflicts the associaters is to make them confounded and discensions will take place then wars to let them taste the suffering from each other.
God – be glorified – said in the Quran 6: 65
قُلْ هُوَ الْقَادِرُ عَلَى أَن يَبْعَثَ عَلَيْكُمْ عَذَابًا مِّن فَوْقِكُمْ أَوْ مِن تَحْتِ أَرْجُلِكُمْ أَوْ يَلْبِسَكُمْ شِيَعاً وَيُذِيقَ بَعْضَكُم بَأْسَ بَعْضٍ انظُرْ كَيْفَ نُصَرِّفُ الآيَاتِ لَعَلَّهُمْ يَفْقَهُونَ
The explanation:
(Say [Mohammed to the idolaters]: He [God Almighty] is All-Able to send forth upon you, [associaters,] chastisement
>> from above you [like storms, hurricanes and plagues]
>> or from under your feet [like earthquakes, volcanoes and floods],
>> or to confuse you in sects and to make you suffer of the violence of one another [conflicts and wars will take place.]
Behold [ Mohammed] how We turn about the revelations; haply that they may understand.)
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Now, both Iraq and Iran people have much enthusiasm about the family of Prophet Mohammed - salam be to him.
So they glorify his sons and sanctify them and make the servitude shared between
God the Creator and between the imams: the descendents of Ali and Mohammed's daughter.
And because of their enthusiasm, they fell into some idolatry and polytheism, and they deserved God's punishment. The reason for this misguidance is because of their wrong-doing: they wrong each other and they disobeyed the apostle of God while he invited them to devote themselves to God alone.
See about such association with God and polytheism here:
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