They are idealists who abandoned their jobs for the battlefields of Ukraine, looking for a cause or simply to fight. The Ukrainian president’s call for foreign volunteers to join an international brigade to help bolster his country’s defense with a new layer of resistance to Russia’s invasion is for now a ragtag army. Recruits say they are often waiting for weapons and training, leaving them feeling exposed. “Pure hell: fire, shouting, panic. And a lot more bombs and missiles.”