[FredZarguna]

Yes, we have.

The exact number of 50+ KT tests conducted by the United States will never be known, but the Mark 6D Bomb was a pure fission device, with several of the higher end models estimated to be 80KT, 154KT, and 160KT respectively.

We know for sure that Ivy King was a 500KT pure fission test detonation, done in prep before Ivy Mike, the first "Super."

In the typical history of these things, a miniaturized thermonuclear device is never the first test. You would expect a several megaton detonation for the cherry pop.

I think it's almost certainly baloney.

[Mariner]

"In the typical history of these things, a miniaturized thermonuclear device is never the first test. "

Unless there was a technology transfer.

I stand corrected on the historical size of fission devices. They would have to be huge for that yield.