I didn't realize depleted uranium was radioactive, but it certainly is:
Depleted Uranium | US EPA.
However, I'm certain Russians use it or worse, not that two wrongs make a right. I think the purpose is the density allows better penetration to destroy enemy armor. Also, my wife is from Pine Bluff, Arkansas which has Pine Bluff Arsenal and was where we were burning up our chemical weapons. My father in law had a special radio in case anything ever went wrong in the demolition process. I don't know how much was destroyed, but it took years. I actually visited the site and they had "shoot on site authorization" warning signs up on their fences, which I assume was to keep terrorists from grabbing nerve agent or mustard gas or whatever they were burning, so I don't think the US has chemical or biological weapons anymore, though we have plenty of nuclear weapons and we need to modernize them because Plutonium becomes unstable after 50-70 years, and most of our nuclear warheads are getting about that old, so for purposes of deterrence (God forbid we ever use them) the US must modernize to keep China who is attempting to reach 2000 warheads and Russia which has 7000 warheads in check.