Re: What if no Manhatten Project

Don't tell me,  the study was done at a time when the US nuclear industry
needed more funds...

Well for what it's worth the declassified Dropshot study which dealt
with a 1955-56 non-nuclear WW3 in Europe and Asia reached the
conclusion that the Soviets were likely to take all Europe and Asia
(though much of it would likely capitulate peacefully once Europe was
in Soviet hands) though it was unclear whether who would hold the UK.

The conclusion was that the United States was unlikely to "prevail" in
such a war without the use of nuclear weapons.

Question whether the post V-E day effort would be minimal, certain
areas like B-52 and B-36, nuke submarines, ballistic missiles all got
boosts over fears of Soviet expansion. Dominos.

Not in the sense of who won or lost.
But the use of the Bomb ended the
war a lot sooner than if it had been
necessary to invade and conquer
Japan on the ground. Hundreds of
thousands of additional deaths
would have occurred.

People were dying in large numbers
in Japanese occupied China and
SE Asia. Public health was on the
verge of collapse in Japan, with
massive outbreaks of typhus and
cholera threatening. The Soviet
campaign in Manchuria and Korea
was quite destructive. The continued
fighting and skirmishing in the
Philippines, New Guinea, and the
South Pacific was drawing blood.
There was a huge British campaign
in train to liberate Malaya. Japanese
HQ was contemplating the wholesale
slaughter of all PoWs and possibly
of all civilian internees as well.

All this is in addition to the enormous
casualties that would be almost
certain if the Allies invaded Japan.

So "the outcome" was deeply
affected by the Bomb.

Stalin was not in any particularly
aggressive mood at the end of the war.
He took what he was given (a lot),
helped Mao take China. It's not clear
how much he was deterred by the U.S.
Bomb and how much by the sheer
exhaustion of the USSR by WW II.

Probably around 1950 in the USSR.
Soviet scientists were speculating
on the possibility of atomic weapons
in 1940. In 1942, a young scientist
in Army service wrote to Stalin urging
research into what might be a war-
winning weapon. Stalin met with the
leading physicists; they told him the
Bomb was possible but probably
not achieveable during the war.  So
he decided to set up a paper project
to be activated after victory.

This decision may have been
influenced by intel from Soviet spies
in the Manhattan Project, which
provided confirmation - the Americans
and British thought it was possible too!

However, even with intel from the
successful MP, the USSR took until
1949 to build a Bomb. Without that
intel, it takes longer. And there is a
possibility that Stalin purges physics,
as he did biology, in which case the
Soviet Bomb is set back many years.
(OTL, Stalin _knew_ the Bomb was
for real, and left physics alone.)

Bomb projects in the US or UK won't
get much support after V-E Day if
they aren't already showing promise
of success. Besides the difficulty of
getting the necessary budget in
peacetime, a large proportion of key
scientists in the field would oppose
the project on pacifist grounds. OTL
they supported it out of fear of Nazi
Germany; that's gone.

I am reading a bio of Szilard.

I get the impression that a wrong turn or two in the early efforts to
engineer the nuclear chain-reaction might have led to no big US A-bomb
development effort during the war.

The Bomb was not important for the outcome of WWII.   But I guess it
might have slowed down Soviet agression in Europe and W. Asia.

If the project was delayed and there was no big push during WWII,
then when would the Bomb have been first tested, if ever?