There is a way to defeat the Islamic State group in Iraq. It's to grant the country's Sunni population its own separate state, free of control from Baghdad. The idea of a "Sunnistan" isn't new, but as American advisers and their Iraqi allies prepare for the crucial battle of Mosul, now is the time to revisit it.
Losing the country's second-largest city would represent a major blow to IS in Iraq. But recent Iraqi history has taught us that without a proper strategy for the "day after" in Mosul, the group is likely to re-emerge in one form or another.
It's not going to be easy. The Sunni experience in the post-Saddam Hussein era has been brutal and won't quickly be forgotten.