Earlier quoted context omitted.
Here's the real reason nuclear power did not succeed in the US (I can't speak of other countries). It was opposed by the Democrats, and the Republicans, although some in favor of it, decided they don't want to spend whatever political capital they had on this. Now both Democrats and Republicans are pro nuclear power. You may not like it, but nuclear power is having a comeback.
The last time to start nuclear to address climate change was the mid-2000s. And we did start four reactors, with many more planned! However they are all construction failures, and the two at Summer were actually even abandoned half completed, it was so bad. And executives our going to jail for their lies during the construction process. That's what I mean when I say nobody knows how to build it. We will likely never…
We do, but those options are not enough. If they were, the Democrats in Washington would not have turned pro-nuclear.
They saw the numbers. You can store electricity from day to night, but not from Summer to Winter. Months-long electricity storage will never make economic sense (or at least not in the next 30 years).
Nuclear reactor construction is currently a decades-long affair. Can we make it shorter?
Here's a little historical tidbit: in WW2, when the Liberty ships started being built, it took the first such ships about 250 days to be built. They took down that number to 150, then to 105, then to 71, then to 30 and then to 10. They even built one in less than 5 days, and that one did survive the war, and kept working until 1963.
The secret was to build large components separately, each on its own assembly line, and then to just snap them together as a giant Lego toy.
The fact that current nuclear reactors take 20 years to build is not a mathematical proof that any design will take as long. It is entirely possible for SMRs to be build in a matter of months, maybe, just like the Liberty ships, in a matter of days. If the politicians in Washington want to make that happen, then the engineers can make it happen.