I honestly fail to see what the fuss is about.
I spent the better part of a decade in an army that derives it's traditions and uniform regulations from the British Regimental system. Sikhs (the folks that are required by their religion to wear turbans - and are very definitely NOT muslim) have had beards and have worn turbans while in British military uniform since the 19th century. If you want to see an example of what the Sikh warrior mindset is about, look up the battle of Saragarhi. 21 Sikh soldiers fought to the death against 10,000 Afghan tribesmen because they didn't feel like surrendering. (as an interesting bit of trivia, 600 Afghan bodies were recovered from that battlefield)
Sikhs wearing turbans have fought and died side-by-side with my forefathers. Sikh blood was spilled in the cause of freedom on the Western front in World War I. Sikhs fought and died in Malaya, Burma, and Italy in WWII.
When I was on active duty, I can recall that in the appropriate section of the uniform regulations, there were specific instructions (and diagrams) for the wearing of turbans, and the correct method to affix insignia onto the front of the turban. Yes, I understand the concept of "uniform" - and that it is perfectly appropriate for every soldier to be uniformly in compliance with the uniform regulations.
As an interesting aside, my military service also included people other than Sikhs being authorized to wear beards. As a recognition of the incredibly hazardous trade they had chosen to take on, Assault Pioneers were permitted to wear beards. For those of you that aren't familiar with the term, those guys are the members of an infantry battle group specifically tasked with clearing enemy obstacles under fire during a deliberate attack. Kinda like these guys:
I figure that is there is over 100 years of precedent for Sikhs displaying courage and loyalty while shedding their blood while wearing a turban, then there shouldn't be any reason that the same thing can't happen in US military service.