The USA controls ICANN and IANA, who together control the DNS root, as well as controlling all so-called "generic" TLDs through ICANN. Only some country TLDs are actually outside of US jurisdiction, as many of the delegate to USA-based registry providers. ICANN/IANA still control whether or not those countries even get to have domains, so the USA could decide that if the Netherlands wouldn't block motherless-dot-nl then .nl shall no longer exist.
DNS being centralised in the USA was potentially problematic when they weren't abusing their power. Now that they are actually abusing their power, it is actually problematic.
ARIN is also a US non-profit corporation, located in Virginia, but the people who run RIPE and APNIC and AFRINIC might disagree that the Internet is entirely "controlled" by Americans.
Yes, my point was the dns isn't the "whole" internet. I know network engineers at some major ISPs that would still find a way to communicate with each other if a genie waved a magic wand and all dns infrastructure worldwide went "poof".
But also my point was that ARIN specifically is vulnerable to USA originated malicious court actions the same as verisign is.
Verisign continually responds to requests. ARIN traditionally doesn't - it just hands out numbers. But we'll see how RPKI makes ARIN more similar to Verisign. ARIN could be ordered to delete RPKI records for an AS, kicking it out of the portion of the internet that checks RPKI records - which also happens to be mandated by the US government.
https://youtu.be/iDbyYGrswtg?si=AL91MHC5q5yg2jnA