The Ukrainian military is not only defending their sovereignty and their people, but destroying the military capabilities and revealing the weaknesses of an enemy foreign power - Russia, by the way, is openly hostile to the United States - so what is there to lose by giving them a bunch or surplus hardware to fight with? We get to field test our gear and collect data on it while they fight our enemy for us. I'm not seeing the downside, here. I really just don't understand the arguments against arming Ukraine, aside from a pro-Russian standpoint.