550 tons of yellowcake. Wikipedia says yellowcake is 70%-90% pure U
3O
8. Let's say 80%. So 550 tons of yellowcake would be 440 tons of U
3O
8. The uranium is about 85% of the U
3O
8 by weight. That leaves 374 tons of uranium. 0.711% of uranium is the U-235 which can be used in atomic bombs. That means they had 2.66 tons of U-235. That's enough for about 40 Hiroshima sized atomic bombs. And a lot more if you start building reactors to create plutonium for bombs.
Nope, no WMDs there.
My own calculations figure that they COULD in THEORY, have produced enough PU239 for at LEAST 100, 20-50KT fission bombs..or use them as the primary for Thermonuclear devices.
This is assuming they had “acquired” the proper data needed to reduce the fuel mass and such, boosting and neutron enrichment.