The following picture is the Ottoman coat of the Hilafet - the symbol of Muslim unity. According to a Hadis-I-sheriff Muslims shouldn't die without knowing the name of his/her Halife. Star and crescent are nominated by the scholars of Islam. The coat or flag of the prophet (Peace be upon him) can't be exactly copied for the matter of Edeb (courtesy). We Turks even don't name ourselves Muhammad or Ahmad out of Edeb for if I have these names and people scold me it'll be a insult to our beloved Prophet (PBUH). Instead, we name ourselves Mehmet or Ahmet. Ottoman Sultans called themselves Servants of Haremain (Mekka and Medina), not the Rulers of Haremain for the Prophet was the Ruler of Haremain. They didn't even put their coats there out of respect for Prophet and Hilafe - I - Rashedin. Now, if you want to claim that you know better than them I have nothing to say. If you claim that Muslims dying for the defense and honor of Muslim lands for a thousand years against the Europeans Crusaders under these flags, which are not the symbol of Islam, I have no way to convince you. However, this much we, hopefully, all know - once the Hilafet was gone and all these states were born, the people in the Middle East haven't seen a single day of peace.
As for the events in 1971, indeed, these were all very tragic and unfortunate. When Muslims start fighting each other terrible things happen. Our history is full of such tragedies. Killing of innocent people by Pak military can't be overlooked. Muhajirs from India who settled in East Pakistan were also the victims of mass slaughter and rape, specially before the military crackdown and after the surrender. Pictures showed they were being baynotted to death. Perpetrators from both sides can't ask for sympathy. As a third party, we were very saddened at the break-up of a Muslim country and changing of the flag and changing of a national anthem full of such Islamic symbolisms. Moreover, the rhetorics from the Indian side made it very plane to us their ultimate motives, which, I believe, Bangladeshi people are feeling day in and day out. They started planning for the break-up since 1947. Nehru though it'll be all over within 10 years, but Mountbatten, having Imperial reflexes, gave 25 years. Anyway, it's no excuse if you give them opportunities.
As for that picture, as Muslims from Turkey, we can't resist ourselves from being extremely saddened. People standing there might be laughing but it reminded us of the Treaty of Sevre, where due to the blunder of a few coup loving generals, the last Hilafet was gone. InshAllah, it will rise again from the place it set.
Anyway, best wishes to both Pakistan and Bangladesh.