The fact that a huge amount of money is wasted in one area doesn't justify wasting a smaller amount somewhere else.

But it puts things into perspective. Humanity blows crazy amounts of money on war, entertainment, advertising and the financial industry, within a system where something like two dozen individuals can (collectively) amass trillions of dollars of personal wealth. But $20 billion for fundamental science, spread out among 23 comparatively wealthy nations is too much?

To expand on your point to illustrate how relatively little this is:

Norway alone spends about $6bn on research and development a year for a population of ~5m people... This project will take ~30 years to complete. Norway alone could fund it.

But there's as you say 23 members (and more associate members), and as a CERN member, Norway contributes ~$30m/year to CERN. That's 0.5% of the R&D budget, or about $6/year per person.

This is the highest per capita amount of any CERN member, since funding is determined based on GDP. E.g. the UK pays less than half as much per capita as Norway. As such, it's reasonable to assume that for most members of CERN, funding to CERN takes up less than a percent of their R&D budgets.

It is likely member states would have to pay more for this, but amortized over the project period, we're talking at most double even without an international (beyond the member states) consortium.

And of course it's not only the 23 member states that benefits from this. Overall in terms of worldwide science funding, CERN is a rounding error.

That isn't relevant. CERN isn't a US government project and the US doesn't provide funding. The cumulative budgets of the EDA member states €223 billion in 2018[1].

[1] https://www.eda.europa.eu/docs/default-source/brochures/eda-...

> CERN isn't a US government project and the US doesn't provide funding.

That's news to US taxpayers, which have provided money to CERN projects for decades, including LHC. Half a billion dollars for LHC was considered a lot of money back in 1997 (when US GDP was ~37% the size it was in 2019).

2008: "On Monday, the Department of Energy and the National Science Foundation announced that the United States has completed - on budget and ahead of the September 30, 2008 milestone - its contribution to the Large Hadron Collider (LHC). Under its agreement with CERN, the U.S. contributed $531 million of accelerator components and particle detectors for the LHC."

https://www.aip.org/fyi/2008/us-contribution-lhc-budget-and-...

The US's contributions to CERN are equipment and services rather than money, but indeed they are a big contributor. They are certainly the largest participating country in the LHC by number of scientists.

The US isn't on here:

https://en.wikipedia.org/wiki/CERN#Member_states_and_budget

Cern is European, the counterpart in the US are fermilab, they are highly knitted together.