Oppenheimer & Kurchatov, Teller & Sakharov:
Today marks 58 years since the Enola Gay dropped the Little Boy device on Hiroshima.
I thought it was worth noting that given the current debate on tactical nukes, the yield from Little Boy's explosion was about 15 kilotons, and that current tactical nukes are rated at about 5-10 kt. It surprised me to see that we got to that level of yield in a small package pretty quickly, when you consider that by 1953 we had tested a 15 kt bomb fired from a 280 mm cannon in the Grable test at NTS.
So what holds us back from doing this? Politics, really. Any arguments about treaties are spurious, since the Threshold Test Ban and Peaceful Nuclear Explosion Treaties really only deal with test yields above 150 kt, and the Comprehensive Test Ban Treaty (as well as the other two) always allow testing when "in the supreme national interest."
At least we got away from the "bigger is better" race, and let the Soviets win with their "Tsar Bomba," tested at 50 Mt but designed for up to 100 Mt yields. Yum - I can still feel that one in my bones, and so can you. We all have some of the Strontium 90 from that test in us.