ISIL (Islamic State in Iraq and the Levant) has banned the wearing of the burqa in some parts of northern Iraq where suicide bombers, dressed as women in the all-concealing burqa, have used that disguise to attack ISIL forces. This is not the first time this has happened in Iraq. Some of the founders of ISIL had participated in the establishment of the "Islamic State of Iraq" in late 2006. This was an act of bravado, touted as the first step in the re-establishment of the caliphate (a global Islamic state, ruled over by God's representative on earth, the caliph.) The caliphate has been a fiction for over a thousand years but still resonated with Islamic radicals. Many other Islamic terrorists opposed this move and some used burqas as disguises to move about or even make attacks on members of this 2006 Islamic State.
The original caliphate came apart after a few centuries because the Islamic world was split by ethnic and national differences. Various rulers have claimed the title over the centuries, but since 1924, when the Turks gave it up (after four centuries), no one of any stature has stepped up and assumed the role. So when al Qaeda "elected" a nobody as the emir of the "Islamic State of Iraq", and talked about this being the foundation of the new caliphate, even many pro-al Qaeda Moslems were aghast. But six years later many of those involved in the failed 2006 effort again declared the establishment of another caliphate. With that there was again a lot of fighting between Islamic terror groups, many of them routinely using the burqa as a disguise.
The burqa has frequently been used by Islamic terrorists or even criminals, to just get past security. American troops in Iraq soon figured out how to defeat this by watching what burqa clad people were wearing on their feet. Large (for a woman) feet and footwear more common with men than woman was a giveaway. Also revealing was how a burqa clad figured moved. Female American troops could detect a man in a burqa more easily than the male troops could and a list of tips was soon compiled and distributed. This sort of profiling also made it easier to detect female suicide bombers.
The current ISIL burqa ban is directed at rival Islamic terrorist groups that are sometimes using burqas for suicide bombers but are more frequently using the disguise to get close enough to use a pistol or assault rifle on ISIL checkpoints or throw a grenade.