U.S. Marine veteran Joshua Cooper was safe and sound at his home in Alaska when he decided he had to go to Ukraine to fight.
"It's nothing that I've experienced before. It's a different type of war," Cooper told CBS News.
Cooper, who fought in the Iraq War, says this war is different from the last one he served in because the side he's fighting for is outgunned.
"I expect that we will put a hurting on the Russians and hopefully deter them from advancing," Cooper said of what he expects in the days and weeks ahead. "Putin is picking a fight with a foe that isn't able to combat them without the assistance of NATO and of other countries. And people want to stand up and fight."
Former Royal Air Force serviceman Jordan Davis left a 5-year-old daughter back home in the U.K.
"It is a very tough call," Davis told CBS News. "I don't know exactly why I chose to leave her. I just knew that there was a calling bigger than something I could rationalize to be here."
Cooper and Davis are fighting alongside Ukrainian forces who have been battling a Russian offensive in the Donbas region. The territory west of Popasna, a city described as "flattened" and surrounded on three sides by Russian troops, is the latest frontier against a fierce Russian offensive closing in fast.
Special forces battalion commander Ihor Lapin told CBS News his men have faced a barrage of long-range artillery and mortars. Ukrainian forces said that without more weapons, parts of the region will fall within a week.
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