I didn't understand Ijtehad and all that...and on other side you are saying Secularism is hedonism etc...If Ijtehad can be practised then why not according to modern needs we can declare State being secular?
When we have enough room in our religion for this, state should be secular...It's not against religion...For "Public Good", you can do this...After that you can have all your values borrowed from religion, leaving few things like Minority as second class citizens etc...

You had written about Battle of Badr and Treaty of Madina...I corrected your version of history just.

Religion can't be an adhesive force now...Throughout the history of Muslims you can see a continuous battle between Modharites and Himyarites...With every new century there erupted new factions and Nations with their own versions of Islam. African Muslims, Spanish , Turkish , Persian ,Indians etc etc...Ummayyads,Safvids,Fatmids,Ismailis,Alawids falana dhimkana...And now even sub-continent Muslims are divided into three very different nations...

Now which version of Islam will you apply on state?

Secular state is not something a "Shaitani Charkha"...People have found it's origins from very religion...Believe me...Islam allows you to have a secular state...These are "Wordly Affairs" as I have quoted the hadith...

By the way you are quite intelligent.
Caliph Abdul Malik was reciting Quran when the news of his succession reached him. He shut down the Quran and said "This is my last time with thee; we shall never meet again". He is said to be the most successful Caliph after Muawiya among all the Ummayad Caliphs...

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