This post reflects a popular misunderstanding of the Maginot Line. I don’t think that this fatally undermines the argument, but it still seems worth correcting.
Epistemic status: I am not a military historian, so I am deferring to military historians who write publicly, rather than looking at the academic literature or (even better) the original sources.
Here’s Bret Devereaux (emphasis in original):
As an aside, the purpose of the Maginot Line was to channel any attack at France through the Low Countries where it could be met head on with the flanks of the French defense anchored on the line to the right and the channel to the left. At this purpose, it succeeded; the failure was that the French army proceeded to lose the battle in the field. It was not the fixed fortifications, but the maneuvering field army which failed in its mission. One can argue that the French under-invested in that field army (though I’d argue the problem was as much doctrine than investment), but you can’t argue that the Maginot Line didn’t accomplish its goals – the problem is that those goals didn’t lead to victory.
And here’s r/askhistorians:
The Maginot line was a series of defensive emplacement built by France to prevent a German surprise attack. The goal was to make a line that would be impenetrable by German forces. This would allowed two things, first to force the Germans to attack through Belgium and the low lands, and second to give the French army the time to mobilize its forces to respond. The Maginot line was successful in both of this goals during the German attack. The Germans did attack through Belgium and the low lands and the French army was mobilize and moved to counter the attack along with the British expeditionary forces. The issue the Allied forces encountered was that German forces also attacked through the Ardennes forest south of the main Allied forced and through rapid movement broke through weak parts of the line and encircled the Allied armies.
Military planners in France (and Germany) of the interwar years contrasted the Napoleonic Wars, with their massive decisive battles that took place in a limited area over a few days, with WWI, with its continual grinding attrition over the entire border for years, and decided that they would rather fight in the Napoleonic style than in the WWI style. They wanted the war to be determined in a single giant engagement (like Ulm or Austerlitz or Borodino or Leipzig or Waterloo), because win-or-lose, it was better than what happened in WWI.
The Maginot Line was intended to force the Germans to concentrate almost all of their force in one direction, when they could be met with almost all of the French force, in a single decisive battle. This battle taking place in Belgium rather than on French territory was an added benefit. It was not intended to win WWI—it was intended to avoid WWI entirely.
The Maginot Line succeeded at its goals. The war between France and Germany was decided in a single giant battle, which mostly occurred in Belgium.
The broader strategic planning was flawed, in two important ways. (1) The French field army lost the decisive battle. (2) Most importantly, the French underestimated the German war goals. In WWI, the Germans would have been satisfied with the transfer of some of France’s colonies and for France to pay the German government’s debt. This wouldn’t have been great for France, but it wasn’t existential to the French state. France was not expecting that Germany was planning on permanently occupying Paris. So the cost of defeat was higher than expected. Even with this massive strategic miscalculation, France suffered less than half as many casualties in WWII as it had during WWI.
I have a background in fusion, and I use the phrase “putting the sun in a bottle” when talking to people who know nothing about plasma physics. You’re not wrong that it’s a different reaction, but it’s still the best intuition pump that people have.
If you were trying to explain to a someone from 1000 AD how a modern natural gas power plant works, you’d probably start with a comparison to burning wood or charcoal. Even though it’s not the same chemical reactions, it’s in some ways a lot simpler, and the containment mechanisms are completely different.
Comparing fusion to the core of the sun is similar. It gives people somewhere to start thinking about the problem, and a sense for how difficult the problem is. You then can more easily explain the actual reactions and confinement mechanisms.
This section seems like the most important, and it’s not closely connected to the rest of the article. It also says some things that are wrong.
A fusion reactor will be mostly capital cost—this is true. Exactly how much these capital costs will be once we start building them is unclear. My estimate is that ARC will have similar capital costs per MWh as Vogtle (which is within a factor of 2 of being commercially competitive). The cost of a fusion reactor has fallen by a factor of ~20 since 2018 (ITER vs ARC), so they might become cost competitive.
Construction times aren’t that long: SPARC is taking 6 years, and ARC is planned to take 4-6 years, compared to 2-5 years for natural gas power plants. I also expect this to get shorter as we get better at building them.
Fusion is not being regulated like fission—it’s being regulated like particle accelerators, which can be built inside of hospitals. People working on fusion are well aware of the regulatory environment, and have been (successfully) working to have reasonable regulations.
It’s very possible that fusion won’t be economically competitive in 10 years (even ignoring AI). We might not be able to get the capital costs down enough. They might require too frequent expensive maintenance. Getting the tritium breeding blankets to work might be harder than expected. But these also might not be that bad, or we might be able to solve them, and then fusion will be economically competitive.
I don’t think that we can say confidently that fusion will be economically irrelevant.