Editor's Note: (Retired Lt. Gen. Mark Hertling is a national security, intelligence and terrorism analyst for CNN. He served for 37 years in the U.S. Army, retiring as the Commanding General, U.S. Army Europe and Seventh Army. The opinions expressed in this commentary are solely those of the author.)
(CNN) I have served for nearly four decades in the U.S. Army, and I have repeated the oath of office to those receiving a commission or being promoted, or the oath of enlistment to those entering our force, hundreds of times. It is a beautiful and unique oath.
Unlike with other armies of the world who pledge to defend their monarch or their homeland, our oath of service links our military to the protection and defense of the Constitution and the obedience to the President under the condition of adherence to orders.
In effect, through that oath the U.S. military defends our people's security while also defending ideas, ideals and the rule of law.
Throughout a career, every soldier -- from private to general -- undergoes training in history, legal processes and values. That training complements what we do on rifle ranges or in field exercises. Soldiers have terrific skills, and they are thinking protectors of the American way of life.
I was in combat for more than three years of my career; during that time, I saw some horrible things and many of those revisit me in dreams. There is evil in man, and in battle. But in the U.S. military -- while there have been occasion where soldiers needed to be disciplined for violating the laws or the regulations -- overwhelmingly and consistently the actions of my brothers and sisters in arms has made me very proud.
That's why, during a recent presidential debate, I had such a visceral reaction to one candidate who stated that the those who serve in the U.S. military would blindly ignore their oath, their training and their conscience to follow what were clearly illegal, unethical and immoral orders. When pressed, that same candidate implied that his personal and directive and leadership prowess would prevail.
It wouldn't.
Even though that same candidate has now tempered those words with a press release and several tweets, as a professional soldier I picked up the "intent" the first time I heard it. And it scared me.
I know our soldiers, and I know our military heritage and the American way of war through study and experience. When well-led and well trained, Americans who wear our country's cloth are pure in spirit and decisive in purpose. They will go where they are sent, fight where they go, and do everything to win where they fight. And they will do it like no other soldier on the globe, because that is who we are.
The profession of arms demands much. Most of all, being a uniformed member of the military of the United States requires unmatched skills, but also a strong character, a honed intellect, an understanding that there are limits to what civilians ask us to do. When the orders we receive from a civilian authority pass legal, ethical or moral boundaries, any soldier of any rank has the right and the duty to first question those orders to receive clarification, and if necessary disobey them if they cross the line. That's what makes us different.
We expect our presidential candidates to differ in their approaches or ideas. But no matter who is the President, that person never has the authority to "order" members of the Armed Forces to violate the Uniformed Code of Military Justice, their ethos, their oath or the international law of land combat. This is just one more thing candidates must consider when determining national security policy.
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