I understand that United States holds only 4% of the world population. But the major point of concern is that, US is also a crypto mining powerhouse of the world. So it is important to have a government who is friendly to cryptocurrency.
Even if the US was to ban mining (the Warren AML law project would be a "de facto" ban because it would simply not be fulfillable by miners) miners would simply rearrange in other countries. Some Chinese miners are said to be still active via VPN, even if mining is banned there. Technically Bitcoin would be fine after a few difficulty adjustments, just like in 2021 - 2021 was even worse than an US ban would be because the Chinese mining sector had more than 50% of the world's hashrate back then.
It could still have an impact as some US mining companies are now publicly traded, and their stocks going down the drain would for sure also pull the Bitcoin price down. However, as at least some of these companies are also selling other datacenter services (cloud, AI ...) they would not necessarily disappear. In general I'd expect consequences to be similar to the 2021 Chinese mining ban, i.e. a likely price drop but then normalization.
They only make up 4% of the world's population but their GDP accounts for nearly 30% of global GDP, the US financial market capitalization is over $50 trillion, which means they dominate nearly 50% of the global financial market.
I've waited for this argument
My point here is actually that the US is a major part of the present of Bitcoin's adoption, but the future depends more on the development in other countries. The EU for example has only a slightly smaller economy than the US but the crypto penetration there is lower and has thus more possible upside.
Then we have of course developing countries like India, where the GDP grows way faster than in the US. India is actually an interesting case because according to estimations it has the most crypto users of all countries (90 million) but the Bitcoin sector is also being held back by high taxes and relatively strict regulations. And if China returns to a even slightly friendlier policy (e.g. allowing local exchanges again) that would also be much more impactful than any US government measure (besides of a complete ban perhaps, which I think would not be constitutional in the US).
Bitcoin will be fine no matter who wins the election but the point is if we have an open government with more bitcoin friendly policies then its development will happen faster and smoother.
I believe with "development" you mean its adoption? Because technical development is quite international already. And the US has strong enough guarantees in its constitution that open source programming cannot be punished (see also the Tornado Cash case, they had to find other reasons for the detention than just programming).
In terms of adoption, it is possible that a crypto-friendly government can help with that locally. But even in El Salvador adoption isn't much more widespread than in other Latin American countries. As I wrote in the OP already, the US has a quite high adoption already with 15-20% of the population having held crypto (not necessarily Bitcoin).
The influence is there, Bitcoin being banned in the US would mean backward 10 years, not counting the ripple effects.
A complete US ban would indeed be quite a heavy hit. But I believe this to be impossible due to the US having quite good protections of basic human rights (free speech for example could be used as an argument against a crypto ban), even if the government or Congress was willing to ban it it wouldn't be easy. And the 50 million crypto holders are quite an argument to not even try it.
