Interesting fantasy, but I don't buy it. Depleted uranium anti-tank rounds are unitary items; you don't assemble the projectile and the propellant casing in the field. They are like items of ammunition. If a stockpile is hit, the propellant will develop a secondary explosion. If the environment is severe enough, the uranium will CATCH FIRE. That is one of the properties it exploits as an anti-tank round: upon penetrating the tank armor, it diffuses as a spray of molten metal inside the tank and, being pyrophoric, ignites upon exposure to air. The whole tank interior becomes a fireball. A bomb hit on a lot of uranium would be much the same as a bomb hit on a lot of magnesium: intense fire and production of metal oxides from combustion. And being carried off in the updraft. And in the case of depleted uranium, being radioactive (not by much).
No need to speculate on a low-yield tactical device. Not clear how the aging of plutonium is meaningful, as Pu-239 has a decay half-life of 24,000 years, and merely transforms into U-235, another bomb fissionable material.
Interesting fantasy, but I don't buy it. Depleted uranium anti-tank rounds are unitary items; you don't assemble the projectile and the propellant casing in the field. They are like items of ammunition. If a stockpile is hit, the propellant will develop a secondary explosion. If the environment is severe enough, the uranium will CATCH FIRE. That is one of the properties it exploits as an anti-tank round: upon penetrating the tank armor, it diffuses as a spray of molten metal inside the tank and, being pyrophoric, ignites upon exposure to air. The whole tank interior becomes a fireball. A bomb hit on a lot of uranium would be much the same as a bomb hit on a lot of magnesium: intense fire and production of metal oxides from combustion. And being carried off in the updraft. And in the case of depleted uranium, being radioactive (not by much).
No need to speculate on a low-yield tactical device. Not clear how the aging of plutonium is meaningful, as Pu-239 has a decay half-life of 24,000 years, and merely transforms into U-235, another bomb fissionable material.