The anti-insurgency strategy that the United States adopted in Iraq was a three-step process known as "clear, hold and build."
Marines like me did the clearing and holding of towns throughout northwest Iraq. Over the last few months, we've been watching closely as ISIS tears apart what the United States and our allies hoped to build in the region.
While most of the media coverage has centered on the larger geopolitical questions related ISIS's rise - along with the domestic political implications - those of us who served are more concerned about those we knew on the ground.
When you embed with a population, even during wartime, you become incredibly attached to the locals who reach out to help you. I got to know a lot of Iraqis who I feel close to even today - some were soldiers, some were civilians, but all were hopeful that we could help them foster a more secure future.
In the midst of the outright brutality of war, families would offer me bread and Chai. Early morning house-to-house clearing would sometimes not just be met by bullets and resistance but also by invitations to breakfast with a whole family.
Even as I grew to believe that the war was wrong for the United States, I remained hopeful for a free, prosperous and Democratic future for Iraq. But watching ISIS roll through towns I patrolled has been crushing.
Many of us have made our individual peace with the fact that we didn't agree with the strategy behind the war in which we served. But there is a distinct pang that comes with watching coverage of ISIS terrorize Iraqi towns.
Could we have better prepared the populace? Could we have left in a way that made the region more secure? Could I, personally, have done more to change the outcome?
These are questions without answers. And yet, I've been reaching out to my fellow Marine Corps veterans with whom I served in the region, looking for their insights and absorbing their thoughts.
One man's thoughts in particular caught my attention, and best framed how I feel about having served in areas ISIS now controls.
I served with Nathan James Huffman in the same battalion and worked together to clear the city of Hit, which recently fell to ISIS fighters. Despite that shared service, I have never met him. But I have been following his blog since he began sharing thoughts about his service last year.
Below is what he wrote the night Hit fell. It has stuck with me.
Tonight Iraq has come home. Not because the city I fought to keep out of the hands of people like ISIS has fallen to ISIS, but because of the human faces in that town. I care about these people. I fought for these people. My brothers fought for these people. Some of my brothers died for these people. They are members of our shared humanity...
To my brothers of 3/25, lift your heads high, there is no reason to feel shame. To the people of Hit, Iraq; you are heavy in my heart and mind.