I am not a nuclear scientist or a physicist.
Here I put forward a layperson argument that I hav e heard or read about.
I do believe some are quite valid.

I also think arguments based on "in the future it is safe" because
we have brand new safe reactors. People make mistakes.
Those are hypotheticals, until new architecture reactors have been
running for say 40/50 years

Nuclear energy is not a renewable form of energy.

If we use today's reactors the supply of economically viable uranium extraction
is small enough that one should worry about it.

There is plenty of uranium that can be extracted available.
From the ocean for one.
Presently that si not economically viable, and the environmental impact
from large scale uranium extraction from the ocean are unknown but likely
to be quite disruptive.

There are designs like Molten Salt that solves the fuel problem since they can
use spent uranium from regular reactors as fuel.
This extends the availability of uranium fuel to such an extent that we dont have
to worry about it.

The biggest problem is what the US conclude in the 60?, 70? that corrosion
from salt is a huge problem and a new alloy is needed to safely contain it.
Or it will require continuing, probably remote only repair, reinforcement
for the reactor to safely operate.

Then there is the problem that no such large scale reactors exist.
I think Russia might have a small one.

There are applications in now to build some.
I dont know if they have been approved or not.

Given that it would be a new type of reactor, with new issues to be solved,
I think we (world) should build one, and let it run for 40 years to
learn from it.

Move fast and break things is not a good approach to nuclear reactors.

Pro Nuclear when confronted with the disasters that we know have happened
the argument is

a) The new reactors will be a lot safer.
Really? They could not have new "bugs" that need to be addressed?

b) Not a lot of people have died from nuclear but so many die for other fuels.
This relies on a model of what fossile fuels may cause to happen over time.
It is cumulative and not directly attributable.
If I stand next to a busy highway near a coal powerplant I will not die from it.
If I do so repeatedly over a long enough timescale it will impact my health,
so will unhealthily eating, no exercise, smoking.
Humans will in general die from combinations of these.

Using the same argument, the other way people are still dying
from Fukushima and Chernobyl. No it is not immediate and there are
other factors, but occurrences of cancer and other related problems
must be measured over a long timescale.

c) In so far as we can make safer nuclear powerplants, we can construct
fossile fuel power stations that produce far less harmfull emissions.
Exactly what to do with the CO2 and other pollutants is a problem.

c) WAR. We have been hit with a barrage of scenarios that will happen if a
Russian missile or such blows up a nuclear powerplant, or several of them.
Should we take that into accounts.

d) If it is safe, then there is no reason to curb other sovereign nations from
building out nuclear power without being hacked, bombed, and so on.

e) If it is safe, how about getting a house in the middle of the desert and
and have it stored in the yard and outhouse. Nobody really wants to do that.
Safe storage of civilian spent fuel in Nevada even got stopped.
We bury it im the ground and let someone else deal with it.
(Which is also true with carbon capture)

f) Spent uranium used as ammunition have shown drastic negative impact
of the health of people who live in those areas afterwards.
Saying something about the dangers.

f) nuclear plants have so far had reasonably short lives.
I think 50 to 80 years.
Then you have real estate that cant be reused for other purposes.

Fossile vs Nuclear is a bit like picking your poison.
Neither seem like an excellent idea overall.

We also saw big problems in Europe last year, were
France had 50% of their nuclear reactors shut off for
overdue maintenance.

Sweden shut down one as well.

Leaving a large gap between available energy and needed energy.
When combinved with shutting off fossile fuel plants and later
on the war in Ukraine which took Russian gas off the table in
different ways.

Europe was lucky they could start fossile fuels up again as
a fall back.

I do think the French problem with their simulations shut down
of so many reactors was an orgy of bad planning rather than a
directly attributable to nuclear energy.

It does highlight that the older the plants get, the more effort
needs to be put into keeping them safely running.

When discussions like these come up on Internet forums they are
usually quickly filled with strong pro-nuclear reactor activists.
I find that a bit odd, and to the extent the forum allows it
other voices are voted out, or certainly drowned out.

I am not a nuclear scientist or a physicist.
Here I put forward a layperson argument that I hav e heard or read about.
I do believe some are quite valid.