As most true heroes will tell you, if you can get them to talk about themselves, they are drawn to running toward the fire rather than away from it — not because they possess extraordinary courage or remarkable strength but because of deep sense of purpose.

One week ago, a handful of strangers that included Vlad Finn, Tyler Merritt, and a small group of U.S. veterans volunteering with the Aerial Recovery Group walked across the border of Poland into Ukraine at the exact moment the sirens were blaring for the nightly curfew.