Atom bomb dropped in Europe

Two different types of bombs were dropped to study the different attributes of Plutonium and Uranium bombs.
The Hanford and Oak Ridge reactors both came online shortly after Nagasaki and IIRC, the US had 12 bombs in its inventory summer of '46. I'm pretty sure if the Trinity bomb is "field tested", the US could drop a total of 5-6 bombs by Christmas if the situation warranted. Bomb production could have been rushed.
A Mushroom cloud over the Reichstag would have most likely ended things quite quickly.

 

You can't rush a-bomb production. If you could, half the nations of the earth would have them.

 

HUH?
Constructing the reactors is the most difficult thing, hard to rush. Once the reactors are online production can be varied widely.
Safety vs. Production
Decreace safety, increase production, and vice versa. Early on fissionable material was produced at a minimal rate due to lack of experience and extremely tight safety margins. Production could easily have doubled or tripled easily while likely not that big of an increase in hazard.